Silica Sol Binder for Building Materials

The use of sodium silicates as gluing binders is limited by the fact that the tensile strength of these bindings is below 50 kg/cm2, and the fact that the bindings remain water-soluble till the annealing temperature of +250°C. Besides, when heated to +160°C , these gluing binders distend. Gluing binders based on SiO2 sold or gels exhibit tensile strength above 500 kg/cm2, are insoluble in water at the annealing temperature of +150°C and do not distend during heating

Self-propagating High-temperature Synthesis of Materials Based on Tungsten Carbide for One-Pot Hydrolysis-Hydrogenolysis of Cellulose Into Ethylene Glycol and 1,2-Propylene Glycol

Методом самораспространяющегося высокотемпературного синтеза из смеси оксида вольфрама, металлического магния, технического углерода и CaCO3 с использованием механохимической обработки получены каталитические системы на основе карбида вольфрама (WnC), содержащие преимущественно W2C. Показано, что фазовый состав образующихся материалов зависит от количества CaCO3. Каталитические свойства полученных материалов исследованы в реакции гидролиза-гидрогенолиза целлюлозы до низших полиолов (этиленгликоль (ЭГ) и 1,2-пропиленгликоль (ПГ)). Установлено, что в присутствии WnC основными продуктами реакции являются ЭГ и ПГ с соотношением ПГ/ЭГ – 1,5-1,8. Нанесение наночастиц никеля на поверхность WnC материалов повышает скорость реакции и выход целевых продуктов. Максимальный суммарный выход диолов составил 47,1 мол. %Catalytic systems based on tungsten carbide (WnC) containing mainly W2C were obtained by the method of self-propagating high-temperature synthesis from a mechanochemically activated mixture of tungsten oxide, metallic magnesium, carbon black and CaCO3. The phase composition of the formed materials was shown to depend on the amount of CaCO3. The catalytic properties of the materials were tested in the hydrolysis-hydrogenation of cellulose to ethylene glycol (EG) and 1,2-propylene glycol (PG). It was established that in the presence of WnC the main products of the reaction were EG and PG with a ratio of PG/EG – 1.5-1.8. The deposition of nickel nanoparticles on the WnC surface increased the reaction rate and product yields. The maximum total yield of diols was 47.1 mol. %

Use of ultra-fine powder of refractory ceramic materials for improving quality of cast-iron castings (ingot moulds)

Translated from Russian (Thermich. Plasm. i Tekh., Institute of Theoretical and Applied Mechanics, Russian Academy of Sciences, Novosibirsk 1999)Available from British Library Document Supply Centre-DSC:9023.190(9588)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Use of ultra-fine powders of refractory ceramic materials to improving quality of cast-iron castings (ingot moulds)

Translated from Russian (proceedings of conf. Thermal Plasma 98, Inst. of Thermophysics, Russian Academy of Sciences, Novosibirsk, 1998Available from British Library Document Supply Centre-DSC:9023.190(9440)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Vacuum performance of a carbon fibre cryosorber for the LHC LSS beam screen

A new carbon fibre material was developed at the Institute of Solid State Chemistry and Mechanochemistry at the Siberian Branch of the Russian Academy of Science (SB RAS) to meet the large hadron collider (LHC) vacuum chamber. The material must have a large sorbing capacity, a certain pumping speed, a working temperature range between 5 and 20K, a low activation temperature (below room temperature), a certain size in order to fit into the limited space available and it should be easy to mount. The vacuum parameters of the LHC vacuum chamber prototype with a carbon fibre cryosorber mounted onto the beam screen were studied in the beam screen temperature range from 14 to 25K at the Budker Institute of Nuclear Physics SB RAS. This carbon fibre material has shown sufficient sorption capacity for hydrogen at operational temperatures of the beam screen in the LHC long straight sections. It is also very important that this material does not crumble and makes a convenient fixation onto the beam screen in comparison to the widely used granulated charcoal. The problem of fluff and ways of reducing the quantity of fluff in the beam channel were studied. The results of these studies show that the carbon fibre material is a possible cryosorber-candidate for use in the LHC and other long vacuum system at cryogenic temperatures. The experimental set-up and results of measurements of the H//2 cryosorption capacity of this carbon fibre material are presented in this paper

Using ultrafine powders of ceramic materials for improving quality of castings

Translated from Russian (Thermal Plasma Torches and Technologies, Nauka, Novosibirsk, 2000)Available from British Library Document Supply Centre-DSC:9023.190(10517)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo