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Correlation of Acoustic Emission Signals with Kinetics of Fatigue Crack Grouwth in the Shock Absorber of Aircraft Landing Gear
No full textRape Seed Oil Tetrahydrofurfurylesters
No full textThe transesterification of vegetable oil using various kinds of alcohols is a simple and efficient renewable fuel synthesis technique. Products obtained by modifying natural triglycerides in transesterification reaction substitute fossil fuels and mineral oils. Currently the most significant is the biodiesel, a mixture of fatty acid methyl esters, which is obtained in a reaction with methanol, which in turn is obtained from fossil raw materials. In biodiesel production it would be more appropriate to use alcohols which can be obtained from renewable local raw materials. Ethanol rouses interest as a possible reagent, however, its production locally is based on the use of grain and therefore competes with food production so it would implicitly cause increase in food prices. Another raw material option is alcohols that can be obtained from furfurole. Furfurole is obtained in dehydration process from pentose sugars which can be extracted from crop straw, husk and other residues of agricultural production. From furfurole the tetrahydrofurfuryl alcohol (THFA), a raw material for biodiesel, can be produced. By transesterifying rapeseed oil with THFA it would be possible to obtain completely renewable biodiesel with properties very close to diesel [2-4]. With the purpose of developing the synthesis of such fuel, in this work a three-stage synthesis of rapeseed oil tetrahydrofurfurylesters (ROTHFE) in sulphuric acid presence has been performed, achieving product with purity over 98%. The most important qualitative factors of ROTHFE have been determined - cold filter plugging point, cetane number, water content, Iodine value, phosphorus content, density, viscosity and oxidative stabilit
Новый региоселективый способ получения метиламида 2-метоксиметил-3-оксо-2,3-дигидро-7Н-тиазоло[3,2-а]пиридин-8-карбоновой кислоты
No full textElectrode Influence on Bi-Layer GaOHPc:C61(CO2Et)2 and P3HT:PCBM Organic Photosensitive System
No full textProgrammēšanas tehnoloģijas industriālā elektronikā
No full textGrāmatas mērķis ir apskatīt programmēšanas tehnoloģijas pamatprincipus, programmatūras konstruēšanas stratēģijas, sistēmas analīzes klasiskās metodes, kā arī programmatūras testēšanas un uzturēšanas tehnoloģijas. Grāmatā piedāvāts pilsētas elektriskā transporta plūsmu vadības modeļa izstrādes projekts, kas sastāv no sistēmas analīzes daļas, prasību definēšanas un analīzes daļas un projektēšanas daļas
Satelītu rādionavigācijas sistēmas
No full textGramatā apskatītas satelītu radionavigācijas sistēmas: Navstar, GLONASS un GALILEO
Сопоставительный анализ математических моделей усталостной трещины
No full textРанее для учета влияния трещины на упругую податливость стержня использовалось понятие эквивалентного упругого шарнира. На основе применения данной модели предложена методика расчета на прочность и жесткость стержневых систем с трещинами
Single Lateral Channel Aided Inertial Navigation System based on North Channel
No full textInertial Navigation System (INS) block diagram analysis results show that it is possible to create single-channel Inertial Navigation System (1INS) using only one channel from conventional full-channel system - lateral, longitudinal or vertical channel respectively. In the full-channel variant of INS there is a crosslink between channels and for this reason the additional external flying vehicle flight parameter sources are needed for channel crosslink compensation. In the 1INS without these additional sources system error increases significantly in comparison with full-channel INS variant. 1INS lateral channel based on North channel model is offered in this work. Simulation results of this system error model are presented. Different variants of system correction using external velocity information source are offered (heading-aided 1INS). Different models of 1INS with correction are offered, and also error model with different correction variant and its combinations simulation results are presented in this work. Obtained simulation results shows that there is significant accuracy increase of 1INS when using offered correction methods
Study of the Dynamics of Permanent Deformations for the AC and SMA Asphalt Mixtures
No full textAim of the research is is investigation of the rutting dynamics on the dense graded AC and SMA mixtures