General-purpose Products Research Articles

The Development and Application of GTL Technology in Russia

The experience of commercial operation of synthetic hydrocarbon technology in Russia at Novocherkassk Plant of Synthetic Products (NPSP) in Novocherkassk, Rostov region, is integrated in the paper. More than 200 items of marketable general-purpose products have been manufactured at NPSP. Information on the production of syngas from natural gas, synthesis of hydrocarbons, and catalysts for the process is reported.

Circular economy implementation in the development of fire-retardant materials used in construction, industry, and general-purpose products

During a fire, passive fire protection systems are designed to prevent the spread of flames, smoke, and toxic gases. The new fire-retardant (FR) material, used for passive fire protection, is created by combining copolymers (VC–co–VAc) (Slovinyl KV 173) and PVC K70 with expanded graphite and plasticizers/modifiers such as diisononyl phthalate - DINP, diisononyl terephthalate - DINTP, dioctyl adipate - DOA, as well as plasticizers that are synthesized based on tertiary recycling of waste poly(ethylene terephthalate) (PET), 1-hexadecene, azodicarbonamide (ADC), tri(p-cresyl phosphate), epoxidized soybean oil (ESO) and acrylate emulsion (DH50, Ecrylic, or Flexryl, etc.). The obtained material's morphology was examined using an emission scanning electron microscope (FESEM) field. Tensile testing was used to determine the mechanical properties of the obtained samples, as well as Shore A hardness and toughness using the Charpy impact test. All samples obtained were tested according to non-flammability standards. To conform to the new trend of "green economy," the development of novel eco-friendly FRs with improved thermal and mechanical properties will include careful consideration of environmental protection and sustainable development.

Calculation of thermal expansion, glass transition temperature and glass density in the system RO–Al2O3–B2O3–SiO2 (where RO=BaO, SrO, CaO, MgO, ZnO)

Glasses of the system RO–Al2O3–B2O3–SiO2 are used as a base for the fabrication of heat-resistant nonmetallic materials and general-purpose products. The purpose of this work is to develop mathematical models for calculating the temperature coefficient of linear expansion, glass transition temperature and density as a function of the composition of glass in the oxide system RO–Al2O3–B2O3–SiO2 where RO=BaO, SrO, CaO, MgO, ZnO. The disadvantage of the known models is that the range of their application is limited by the quantitative content of components in the glass. At the same time, an increase in the sample size of experimental compositions made it possible to obtain more accurate mathematical models for calculating these properties. The glasses included in the experimental sample are distinguished by a wide range of temperature coefficient of linear expansion (from 30 to 10510–7 К–1). The glass transition temperature of these glasses is within the range of 580–7100C, which allows a reasonable approach to the choice of temperature regime for the formation of the structure vitreous and glass-ceramic materials for different functional purposes. The mathematical models were developed with the use of the experimental and statistical method. The obtained mathematical models are adequate to the experimental data and allow calculating the thermal expansion, glass transition temperature and density of glasses; the mean-square deviations of temperature coefficient of linear expansion, glass transition temperature and density being 1.910–7 К–1, 16.00C and 0.06 g cm–3, respectively. Their accuracy is sufficient for the development of basic glass compositions for various functional purposes.

Mechanical properties of mechanically-defibrated cellulose nanofiber reinforced epoxy resin matrix composites

Cellulose nanofibers (CNF) have recently attracted attention as one of the reinforcements for composite materials. However, the same as other nanofibers, CNFs can be easily agglomerated and the nano-level defibration is necessary to obtain their outstanding properties in polymer matrices. To overcome this issue, two major defibration methods, chemical and mechanical defibration have been considered. The chemically-defibrated CNF is expensive and so prevents the practical realization of CNF as general-purpose products. Therefore, the mechanical defibration method by a clean low-cost water jet was focused on. Mechanically-defibrated CNF reinforced epoxy resin matrix (Epoxy-CNF) composite was fabricated via mechanical mixing and the variation of their tensile and flexural properties with different CNF volume fractions was evaluated. The tensile and flexural moduli of the epoxy resin were increased by CNF addition, while the fracture elongation was decreased. The calculated ultimate tensile strength (UTS) and ultimate flexural strength (UFS) of the Epoxy-CNF composites, using the aspect ratio of the agglomerated CNF clusters, indicated the validity of the random dispersion model considering the agglomerated CNF as one whole fiber. It seems that epoxy resin is enhanced by the mechanical interaction when the CNF volume fraction is higher than 0.37 vol.%.

RESISTANT POLYMER NANOCOMPOSITES’ DEVELOPMENT AND INVESTIGATION

Introduction. The advanced technology development demands higher requirements to the physicomechanical characteristics of the polymer composite materials (PCM) widely used in general and special purpose products such as in transport and road-building. This determines the relevance and significance of the new polymer nanocomposites development on the tribotechnical purpose with high physic-mechanical and tribotechnical characteristics. Materials and methods. The problem mentioned above is solved by means of the structural modification’s methods of the PCM polymer matrix and the technological process optimization of the composite materials’ synthesis. One of the structural modification advanced methods is the polymer matrix charging with different fillers’ types, particularly, disperse and fiber ones, and in recent years – ultradispersed and nanodimensional fillers. Results. The composite materials with nanodispersed fillers feature the properties significantly different from those of the materials with microand macrodispersed particles because of the high surface activity of nanodimensional particles’ fillers. Discussion and conclusion. The research deals with the development results and polymer nanocomposites’ investigation with polydispersed and nanodimensional fillers, their influence upon the structure and wear-resistance of the polymer composite materials based on polytetrafluorethylene.

Niche-Product Offering in the Spokes Model

We use a spokes model to analyze firms' incentives when facing the choices of general-purpose products and niche products. Products at or near the end of the spokes are niche products, while products near the origin are more standardized products that cater to the taste of many consumers. Our results indicate that although a monopolist always offers the general-purpose product, if a firm anticipates entry, it may choose to stake claim to a niche market. For low transportation costs or when consumers do not have strong brand preferences, the early entrant chooses the general-purpose product. But this equilibrium is characterized by aggressive pricing behavior.

Radiation resistance of elastomeric O-rings in mixed neutron and gamma fields: Testing methodology and experimental results.

Materials and components employed in the presence of intense neutron and gamma fields are expected to absorb high dose levels that may induce deep modifications of their physical and mechanical properties, possibly causing loss of their function. A protocol for irradiating elastomeric materials in reactor mixed neutron and gamma fields and for testing the evolution of their main mechanical and physical properties with absorbed dose has been developed. Four elastomeric compounds used for vacuum O-rings, one fluoroelastomer polymer (FPM) based and three ethylene propylene diene monomer rubber (EPDM) based, presently available on the market have been selected for the test. One EPDM is rated as radiation resistant in gamma fields, while the other elastomers are general purpose products. Particular care has been devoted to dosimetry calculations, since absorbed dose in neutron fields, unlike pure gamma fields, is strongly dependent on the material composition and, in particular, on the hydrogen content. The products have been tested up to about 2 MGy absorbed dose. The FPM based elastomer, in spite of its lower dose absorption in fast neutron fields, features the largest variations of properties, with a dramatic increase in stiffness and brittleness. Out of the three EPDM based compounds, one shows large and rapid changes in the main mechanical properties, whereas the other two feature more stable behaviors. The performance of the EPDM rated as radiation resistant in pure gamma fields does not appear significantly better than that of the standard product. The predictive capability of the accelerated irradiation tests performed as well as the applicable concepts of threshold of radiation damage is discussed in view of the use of the examined products in the selective production of exotic species facility, now under construction at the Legnaro National Laboratories of the Italian Istituto Nazionale di Fisica Nucleare. It results that a careful account of dose rate effects and oxygen penetration in the material, both during test irradiations and in operating conditions, is needed to obtain reliable predictions.

MARKET SEGMENTATION STRATEGIES OF MULTIPRODUCT FIRMS*

We analyze a multiproduct duopoly and ask whether firms should offer general purpose products or tailor their offerings to fit specific consumer needs. Offering a targeted product has two effects: utility increases for some consumers due to increased fit, whereas utility decreases for others due to increased misfit. Previous work has not considered these two effects jointly and has therefore not been able to capture the tradeoff inherent in market segmentation. We show that in addition to the degree of fit and misfit, the intensity of competition and the fixed cost of offering an additional product determine firms' market segmentation strategies.

On Hotelling's Competition with General Purpose Products

This paper extends the traditional Hotelling's model of spatial competition by allowing firms to choose the degree of general purposeness of their products before they compete in prices. The degree of general purposeness is approximated by endogenizing the per-unit transportation cost coefficients. The game presents a continuum of perfect Nash equilibria featuring no price competition. In equilibrium, firms behave as 'specialist' by choosing high transportation cost coefficients. This allows them to extract all the marginal consumer's rent and to perfectly segment the market. Moreover, market is entirely served by both firms regardless the value of the consumer's reservation price.

Competing in Markets with Digital Convergence

The last couple of decades have witnessed widespread digitization of information and content, increasing incorporation of digital technologies into the products of diverse industries, and often, an accompanying shift to using von-Neumann-like platform-based product architec- tures. This phenomenon has been termed digital convergence, and has been observed in technology industries as diverse as handheld computing, wireline and mobile telecommunications, consumer electronics, networking equipment, residential broadband and broadcast video. Digital convergence results in substantially more valuable and flexible products and services, but also leads to increased substitutability between products in previously distinct markets. This paper analyzes the economic implications of this trade-off between increasing value and increasing substitutability. We present a new general model of imperfect competition that enables us to capture specific economic aspects that characterize digital convergence — flexible product scope, variability in consumer requirements, and non-exclusionary product choice. We derive four types of equilibrium configurations — local monopoly, kinked, competitive and non-exclusive — that emerge as outcomes of the model, and describe how each equilibrium structure characterizes a distinct stage of digital convergence. Our analysis establishes that as markets converge, prices rise initially even as competing prod- ucts become less differentiated. However, when platform scope is largely dictated by exogenous factors, prices and profits eventually fall as the stage of convergence progresses, though consumer surplus and total surplus rise. Furthermore, while digital convergence has the expected effect of shifting consumption patterns from multiple specialized products purchases to single general- purpose product purchases, we describe examples of equilibria in which consumers may buy mul- tiple general-purpose products, using each for a specialized subset of their requirements. Pricing responses to changes in variable costs and consumer functionality needs are also discussed. When firms can strategically choose platform scope, we show that in any subgame perfect equilibrium, duopoly prices are always higher than monopoly prices, and industries may sustain high levels of profitability even when their boundaries blur.

CARPENTER PROJECT 70+ TYPE 316/316L

Abstract Carpenter Project 70+ Type 316/316L is a modified version of Type 316/316L stainless steel with improved machinability when compared to conventional 316/316L. The alloys are non-hardenable austenitic chromium-nickel-molybdenum steels and are good general-purpose products for simple and complex parts.See also Project 70/Project 7000 Type 316, Alloy Digest SS-339, revised October 1997, and Project 70/Project 7000 stainless type 316L, Alloy Digest SS-515, revised July 1997. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-878. Producer or source: Carpenter Specialty Alloys.

A New Raw Material for Aluminosilicate Ceramics for Refractory and Engineering Use

Topaz-containing raw materials from the Kopna deposit are analyzed for chemical and mineral composition. Beneficiated rocks with different contents of topaz and topaz concentrates are classified as commercially promising for the manufacture of aluminosilicate refractories such as heat insulators and general-purpose products. The role of topaz in the quality improvement of clay-topaz compositions and processes of sintering and phase formation is discussed.

Product differentiation and endogenous disutility

This paper models the choice of degree of focus (or general purposeness) available to firms by endogenizing transportation costs in an address model of horizontal differentiation. The formulation is in three stages: entry, focus or design competition and price competition. The strategic effect of product design is analyzed. The equilibrium level of general purposeness is shown to depend critically on ‘neighbor exclusivity’. The latter and, more generally, market structure and product diversity are shown to depend on the cost of producing general purpose products. If general purposeness is ‘free’—to design and produce—only two firms enter the market and set large transportation costs, underproviding product diversity.

Monopolistic Competition and General Purpose Products

Most models of monopolistic competition study the question of the optimal degree of product differentiation by looking at the number of firms that will locate in characteristics space. This is somewhat restrictive. The development of purpose products means that the needs of quite heterogenous consumers can be satisfied with the same homogenous product. The private and social incentives to produce purpose products are studied in this paper within the circular-road-model of monopolistic competition. The degree of general purposeness of a product is approximated by its per unit distance transport costs. It is shown that there are strong forces leading the market to supply products whose transport costs are excessively low.

COPPER ALLOY No. C33100

Abstract Copper Alloy No. C33100 is a free-cutting tube brass. It has a good combination of mechanical properties. It has excellent solderability and good brazeability. Its uses include general-purpose screw-machine products, pump and power cylinders, plumbing accessories and primers in the munitions industry. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-517. Producer or source: Copper and copper alloy mills.

COPPER ALLOY No. C33200

Abstract Copper Alloy No. C33200 is a free-machining brass containing nominally 1.6% lead. Its machinability rating is 80% of that of Free-Cutting Brass. It has good resistance to corrosion in many environments. Alloy No. C33200 is used widely for general-purpose screw-machine products. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Cu-513. Producer or source: Brass mills.