Using increased fabrication pressures for making articles from certain electrofused highly refractory materials

Conclusions The porosity of refractories made from fused materials can be greatly reduced (to 10–13%) by using increased fabrication pressures and coarse grained bodies with low quantities of finely milled bond (10–15%).The densification mechanism in the coarse-grained bodies consists in breaking up the large grains and redistributing them. The requirement for maximum density of packing in selecting the grain-size composition of the bodies is of first rate importance.The maximum fabrication pressure should not exceed the values at which the critical density is reached.Translated from Ogneupory No.6, pp.49–53, June, 1972.     

Firing technology for refractories made of sintered corundum

Conclusions A technology was developed for firing corundum refractories, which, when used with a batch containing densely sintered chamotte having a water absorption of up to 3%, 40–45% finely milled corundum (minus 60 m), and a fabrication pressure of 100 MPa, guaranteed the production of dense goods, and with the use of slightly sintered chamotte having a water absorption of up to 12% — high-density goods. With a reduction in the fabrication pressure of the green articles to 50 MPa the new technology ensures the production of densified goods.Translated from Ogneupory, No. 5, pp. 15–20, May, 1979.     

Properties and areas of application of chemically metallized chemisorption fibres

The results of studies of methods of fabrication of metal-cluster chemisorption fibres, their conducting and dielectric properties are reported. The proposed areas of application of this type of fibres are examined.Chemical Defense Military. AcademyTranslated from Khimicheskie Volokna, No. 6, pp. 49–51, November–December, 1994.     

The fabrication of polymer microfluidic devices using a solid-to-solid interfacial polyaddition

It is hard to permanently seal the microfluidic channels made of thermoset polymers without using conventional adhesives. Here, we reported a polyaddition-based mechanism to solve the problem. The method is based on introducing amine groups onto the surface of one material and epoxy groups on another material and enabling the amine–epoxide polyaddition reaction at their closely contacted solid-to-solid interface to establish a covalent and permanent bonding. It was successfully used to permanently seal polydimethylsiloxane (PDMS) microfluidic channels with glass in a scalable and multifunctional fashion and to seal epoxy (SU-8) microfluidic channels with PDMS. This type of interfacial polyaddition can be easily extended to other materials for microfluidic device fabrication and is expected to find some applications in specialty bonding.     

Fabrication and prospects for the development of polyester microfibres (review)

One of the promising trends in the development of textile fibres — the creation of technology and equipment for production of microfibres which makes it possible to obtain comfortable new materials was analyzed. The technological characteristics of fabrication of microfibres with two levels of filament linear density were examined: 0.1–0.03 tex by high-speed spinning (HSS) using special techniques, and 0.03–0.002 tex with sector structure based on two-component systems. The stable tendency toward development of new techniques for thinning filaments to create a new generation of textile materials was pointed out.All-Russian Scientific-Research Institute of Synthetic Fibres, Tver'. Translated from Khimicheskie Volokna, No. 3, pp. 3–10, May–June, 1995.     

Basic characteristics of synthesis and technical requirements for fiber-forming polycarbosilanes

These studies showed that the conditions of synthesis and properties of polycarbosilane are a function of the purity of the stating polydimethylsilane, and the technical requirements for its quality were elaborated as a result of this. The temperature—time parameters of synthesis (350–380°C, 3–8 h) and concentration of promoter — polyborodiphenylsiloxane (1 wt. %), were determined for fabrication of stably formed polymers. The criteria for the end of synthesis and obtaining a polymer with the required degree of branching were established. The preliminary technical requirements for fiber-forming polycarbosilane were formulated.State Scientific-Research Institute of Chemistry and Technology of Organoelemental Compounds, Moscow. Translated from Khimicheskie Volokna, No. 4, pp. 16–18, July–August, 1992.     

Manufacturing methods for optically and IR transparent glass ceramics

A method for manufacturing optically transparent sitalls from glasses based on brown coal ashes from the Kuybyshev Automobile and Tractor Electrical Equipment and Carburetor Plant (KATEK) was developed in laboratory conditions. The optical, mechanical, and thermal properties of the transparent sitalls were as good as for quartz glass. They are promising for use as the base for optical and magnetooptic information carriers and in fabrication of band-pass filters in the visible and near IR region of the spectrum.Translated from Steklo i Keramika, Nos. 3–4, pp. 15–16, March–April, 1994.     

Use of azoic dyes for dyeing Terlon fibre

The use of components for formation of azoic dyes in certain stages of fabrication of Terlon fibres allows obtaining dyed fibres with high color fastness and preservation of the basic physicomechanical properties of the fibre.Russian Correspondence Institute of the Textile and Light Industry, Moscow. Avtokhimeks TOO. All-Russian Scientific-Research Institute of Polymer Fibres, Mytishchi. Translated from Khimicheskie Volokna, No. 3, pp. 13–14, May–June, 1995.     

Device for the automatic weight-metering of a liquid

Conclusions -- A simple device made up from standard instruments for automatic weight-metering of liquid with reasonably high accuracy has been developed, stand-tested, and proposed for introduction into pilot plants and into industry.-- The introduction of the metering device in question instead of traditional volumetric metering devices will make it possible to considerably raise the quality of the reaction mixture and to stabilize the technological polymerization process.Translated from Khimicheskie Volokna, No. 5, pp. 54–55, September–October, 1990.     

The application of polycrystalline diamond in a thin film packaging process for MEMS resonators

This paper reports the design, fabrication and testing of a polycrystalline diamond (poly-C) thin film packaging process for a MEMS cantilever type resonator using a 4-mask fabrication process, which integrates chemical vapor deposition (CVD) diamond thin film technology with an encapsulation packaging process. After poly-C cantilever beam resonators were fabricated using the first two masks, a sacrificial PECVD SiO₂ layer with a thickness in the range of 4–5 μm was deposited at 350 °C and patterned to create the package anchor. Then, a 4-μm-thick poly-C film was grown and patterned to create the thin film packaging structure containing fluidic access ports for the removal of the sacrificial layer. The fluidic access ports were finally sealed with an additional poly-C growth. To evaluate the efficacy of the poly-C encapsulation process, poly-C cantilever beam resonators were tested using a piezoelectric actuation and laser detection method before and after the poly-C packaging process. Resonance frequencies measured before and after are in the range of 240–320 kHz, which is consistent with predicted calculations. A modified fabrication process was designed to test the fluidic hermiticity of the thin film package.     

Periclase-Carbon Refractories for Operation in the Mouth of a Converter Vessel

The performance of periclase-carbon refractories cemented with a phenolic bond that are intended for use in the lining of the cone section of the oxygen converter vessel has been studied by x-ray diffraction and petrography techniques. The results obtained provide a basis for further improvement of the oxygen converter technology and refractory fabrication.__________Translated from Novye Ogneupory, No. 2, pp. 23 – 25, February, 2005.Based on materials reported to the 8th Congress of Steelmakers (18 – 22 October, 2004, Nizhny Tagil, Russia).     

Inverse evaluation of the integral ordering of the structure and defectiveness of fibres and yarns for technical applications based on normalized values of the mechanical properties

Methods are proposed for an integral (generalized) evaluation of the degree of ordering of the structure and defectiveness of fibres based on the inverse use of indexes of their mechanical properties — modulus of elasticity and strength — normalized with respect to their maximum attainable values. These maximum attainable values are determined in defined temperature-time conditions for a defect-free polymer crystal by several methods, obtaining values in relatively good agreement. The coefficients characterizing the overall ordering and imperfection of the structure, and the defectiveness of different types of fibres based on linear (aliphatic and aromatic), laminar (carbon), and three-dimensional (silicate) polymers were estimated. Different types of fibres, including fibres of the same type, were compared with respect to the level of structural organization and defectiveness. This could serve as a measure of the perfection of the fabrication processes.St. Petersburg State University of Technology and Design. Translated from Khimicheskie Volokana, No. 5, pp. 34–41 September–October, 1996.     

Spinning of hollow and matrix fibres from polysulfone melt

The possibility of fabrication was demonstrated and the basic technological parameters for spinning polysulfone fibres by the high-production melt method were determined. The polysulfone fibres developed were used as matrix and hybrid structures; thermostable composites with elevated physicomechanical properties were fabricated from such semifinished products.V. V. Gorlov participated in fabrication of the hollow fibres.Translated from Khimicheskie Volokna, No. 6, pp. 29–31, November–December, 1994.     

Ultrastrong fibres fabricated by orientational crystallization from gel. A review

The methods of fabrication of ultrastrong chemical fibres from flexible-chain polymers examined in the review require use of a starting polymer with an ultrahigh-molecular-weight. Attaining ultrahigh draw ratios is a common technological condition. This is almost exclusively determined by the ratio between the deformation rate, temperature, and initial state of the polymer. Gel technology is a priority method of fabrication of ultrastrong fibres. The polyester fibres fabricated by this method attain strengths of 6–7 GPa and Young's modulus of 220–250 GPa. All ultrastrong fibres have the structure of a fibrillar crystallite with a significant fraction of KVTs. All ultrastrong fibres have a melting point 5–10°C higher than for oriented fibres and elevated technical stability with high temperatures and moderate loads.Ukrainian Scientific-Research Institute of Fibres, Kiev. Translated from Khimicheskie Volokna, No. 6, pp. 8–17, November–December, 1992.     

Decorated glass based on slime wastes from organic plants

The possibility of using slime wastes from organic plants for fabrication of decorated glass during synthesis of metal oxide coatings on its surface was investigated. The expediency of using wastes as raw material for film-forming solutions was demonstrated, and the properties of the coatings were reported.Translated from Steklo i Keramika, Nos. 3–4, pp. 2–5, March–April, 1994.     

Refractories for continuous casting of low carbon rimmed steel

Conclusions The compound proportioning device designed by the All-Union Institute of Refractories from an aluminous nozzle containing 80–82% alumina with a porosity of 18–23% and a corundum insert containing 97% alumina with a porosity of not more than 18% satisfies the requirements of continuous casting of low-carbon rimmed steel of the type 05–08KP.Investigations led to the determination of a range of refractories for steel casting and intermediate ladles permitting satisfactory casting in continuous casting plant of low carbon rimmed steel of the type 05–08KP from 140-ton ladles in four shanks with a casting time of about 1.5 h.Translated from Ogneupory, No. 8, pp.4–12, August, 1967.     

Growth and characterization of thin Cu-phthalocyanine films on MgO(001) layer for organic light-emitting diodes

Surface morphology and thermal stability of Cu-phthalocyanine (CuPc) films grown on an epitaxially grown MgO(001) layer were investigated by using atomic force microscope and X-ray diffractometer. The (002) textured β phase of CuPc films were prepared at room temperature beyond the epitaxial MgO/Fe/MgO(001) buffer layer by the vacuum deposition technique. The CuPc structure remained stable even after post-annealing at 350°C for 1 h under vacuum, which is an important advantage of device fabrication. In order to improve the device performance, we investigated also current-voltage-luminescence characteristics for the new top-emitting organic light-emitting diodes with different thicknesses of CuPc layer.     

Review of some specific characteristics of conducting chemical fibers

The analysis of the domestic and foreign publications on conducting chemical fibers showed that their electrophysical properties are a function of the method of fabrication (the temperature-mechanical effects to which they are exposed during spinning, finishing, and processing into articles) than of the composition to a much greater degree. For carbon black-filled fibers containing more than 20 wt. % filler, the specific electric resistance differs by several orders of magnitude even for the same polymer support.All-Russian Scientific-Research Institute of Polymer Fibers, Mytishchi. Translated from Khimicheskie Volokna, Vol. 25, No. 1, pp. 25–29, January–February, 1993.     

Nanodiamond planar lateral field emission diode

We report the fabrication and field emission characteristics of the nanodiamond planar lateral field emission diode. Nanodiamond films with grain size as small as 5–10 nm have been realized through the process of CH₄/H₂/N₂ microwave plasma enhanced chemical vapor deposition (MPECVD) by employing an effective growth rate reduction technique. Well-controlled processes have been developed; including reactive ion etch (RIE) to pattern the nanodiamond films to fabricate lateral field emission devices with planar lateral fingers. An anode–cathode spacing of 2 μm between the nanodiamond anode and cathode has been achieved. A nanodiamond lateral diode equipped with 6 fingers and an inter-electrode separation of 3 μm exhibits a turn-on voltage of 5.9 V (threshold electric field of 1.9 V/μm), one of the lowest reported for lateral field emission devices, and a high emission current of 1.1 mA ( 183 μA current per finger) at an anode voltage of 100 V ( 30 V/μm). The emission current is found to be stable with 4% fluctuation at 1 mA over 10 h. The nanodiamond lateral device is very promising for applications in vacuum nanoelectronics, sensors, and nanoelectromechanical systems.     

Mesoporous silica–magnetite nanocomposites: Fabrication, characterisation and applications in biosciences

Template assisted fabrication of magnetic mesoporous silica–magnetite nanocomposites and their performance in binding and elution of Salmon sperm DNA has been reported. The effect of reaction pH (10–2) during the fabrication of nanocomposites has been studied. All materials fabricated at various pH were characterised by XRD, TEM, FT-IR, nitrogen adsorption and magnetic susceptibility measurements. Fabrication at neutral pH (7) in the presence of a cationic surfactant (cetyl trimethyl ammonium bromide; CTAB) produced core–shell nanocomposites of quasi spherical and rod shaped morphologies with mesoporous (pore size 3.5 nm) silica shell and rhombic magnetite core. Fabrication at alkaline pH (10) produced monolithic mesoporous silica composites with embedded magnetite nanoparticles. Fabrication at acidic pH (4 and 2) produced a biphasic mixture of rhombic magnetite and amorphous silica rods. A similar fabrication at acidic pH (2) in the absence of CTAB produced a biphasic mixture of rhombic magnetite and spherical silica nanoparticles. All materials exhibited a high value of Salmon sperm DNA binding at physiological pH whereas elution value of DNA was observed to be dependent on the extent of silica coating on magnetite nanoparticles.