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11.
Brief information is presented about the state of the world and domestic market of composite materials and epoxy resins as raw materials for polymeric matrices. It is shown that facilities for manufacture of epoxy resins should be created in the country, with a total output capacity of 40–50 thousand tons a year. p-tert-Butylphenol glycidyl ether was synthesized and its influence on the properties of composites based on ED-20 epoxy resin was examined. Dependences of the viscosity, gelation duration, glass-transition point, water-absorption capacity, and hardness of the composites on the amount of diluent were obtained. The results can be used to solve the problem of choosing the diluent in manufacture of composite materials.  相似文献   
12.
The extraction of solketal from aqueous glycerol with AI-92 gasoline, toluene, hexane, and 1-hexene was studied. Aromatic compounds and mixtures containing them exhibit the best extracting properties. A flowsheet was suggested for recovering solketal from reaction products by extraction.  相似文献   
13.
Conditions were found under which the industrial aluminum-platinum catalyst AP-64 and the pilot zeolite system Pd-Zn/Al2O3/MFI (MFI is a high-silica ZSM-5 type zeolite) catalyze single-stage highly selective conversion of rapeseed oil and ethanol to either alkane or alkanearomatic fraction of hydrocarbons suitable as engine fuel components. The hydrocarbon chain grows with participation of ethylene, which is formed in the argon medium directly from the ethanol molecule. Under these conditions, hydrogenation of this alkene on intermetallic clusters arising during the long-term reductive preactivation is suppressed. The alcohol supplies not only ethylene but also hydrogen. In the presence of Pd-Zn/Al2O3/MFI, ethanol is converted to alkanes and aromatic hydrocarbons according to independent pathways. Joint processing of alcohols and rapeseed oil in the presence of the Pd-Zn/Al2O3/MFI catalyst system is an efficient and promising route to C3-C11 hydrocarbons in the absence of an external source of hydrogen.  相似文献   
14.
Physics of Atomic Nuclei - The Carpet-3 experiment for investigation of gamma radiation with energy above 100 TeV is currently being prepared at the Baksan Neutrino Observatory of the Institute for...  相似文献   
15.

Chronicle

Seventy-five years of the Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences  相似文献   
16.

Conversion of oxygenates to aromatic hydrocarbons in the syngas medium in the presence of a commercial zeolite-containing catalyst was studied. The influence of pressure on aromatization of dimethyl ether and ethanol was examined. At 400°C, an increase in the pressure from 0.1 to 3.0–10.0 MPa leads to a sharp increase in the yield of aromatic compounds. Dimethyl ether and ethanol, which are isomers belonging to different classes of compounds, were compared as substrates in conversion to aromatic hydrocarbons. At elevated pressure, dimethyl ether compared to ethanol exhibits higher selectivity in formation of the desired synthesis products, allowing synthesis of liquid hydrocarbons with increased content of arenes.

  相似文献   
17.
Kinetics and Catalysis - The kinetics of hydrogenolysis of glycerol to 1,2-propylene glycol on a catalyst containing 60 wt % copper on Al2O3 was studied. A reaction scheme for the conversion of...  相似文献   
18.
Using the benzene alkylation reaction with propylene, the catalytic properties of heterogeneous catalysts are compared under conditions of simultaneous action of permanent deactivating factors (atmospheric pressure, increased volume feed rate) on the samples under study. For a comparative evaluation of the tested catalysts, a mathematical analysis of the experimental data on the concentration of the desired alkylation product vs. the time of the catalyst operation was carried out, and a corresponding empirical formula was derived. To compare the activity of catalysts, the power coefficient of the function was proposed as a catalyst activity factor f. A relationship between the value of this factor and the rate of deactivation of the catalyst under the conditions of the experiments was derived.  相似文献   
19.
An experiment for measuring the flux of cosmic diffuse gamma rays with energies above 100 TeV (the Carpet-3 air shower array) is now being prepared at the Baksan Neutrino Observatory, Institute for Nuclear Research, Russian Academy of Sciences. The preparations entail a substantial increase of the areas of both the muon detector and the surface air shower array. The experiment’s sensitivity to showers generated by primary gamma rays is estimated for different configurations of the array. In addition, preliminary estimates of the upper limit on the flux of diffuse gamma rays with energies higher than 1.3 PeV, derived using experimental data from the old Carpet-2 array, are presented for a net exposure time of 9.2 years.  相似文献   
20.
JETP Letters - Carpet-2 is an air-shower array at Baksan Valley, Russia, equipped with a large-area (175 m2) muon detector, which makes it possible to separate primary photons from hadrons. We...  相似文献   
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