It was presented IR spectrophotometry method for determination of methyl esters of higher fatty acids of rapeseed oils, in used engine oils, used as diesel fuels. Absorbance measurements of used oils in comparison to new oil and measurements new oil standards with 0 to 20 % of EMKOR, make possible determination of EMKOR concentration in used engine oils with accuracy = +- 5 %. It was used absorption band 1745 +- 5 % cm-1 and as a reference KBr was used. The method was verified on dozens samples, coming from various engines fuelled EMKOR fuel in different service conditions.
The paper covers description of determining possibilities of fatty acids methyl and ethyl esters (FAME) in diesel fuels by use of IR spectrophotometry. Over dozens FAME lots from various manufacturers were tested. FAME content in diesel fuels for concentration range from 0 to 10% was determined with precision < 2%, and for concentration over 10% with precision 5%. The tests were made for band at 1740 cm-1 wavelength with KBr optics use. The obtained results were compared with results obtained by other authors by use of different methods.
Physical backgrounds of the PAS method and its relation with spectrophotometry, gas chromatography and mass spectrometry (GC-MS) have been presented. It was found that there is a correlation between test results obtained by PAS and GS-MS in area of poliaromatic structures.
In the paper it was presented a state of knowledge about biofuels in the world and in Poland, referring to gasoline ethanol and diesel fuel-FAME mixtures, performance characteristics and production methods. It was presented opinion about discussion that took place in relation to the first version of act on biofuels. Considering objective conditions i. e.: social, economical and technologica, critical assessment of opinions presented in numerous publications have been given.
Chemical compositions and basic characteristics of many oil plants have been presented. Modification possibilities of their chemical composition, quality and productivity by use of new agriculture technique and transgenetic materials have been given. Various vegetable oils were estimated in the aspect of application as components and/or additives for fuels, lubricants, hydraulic fluids and other operational fluids.
Chemical compositions and basic characteristics of many oil plants have been presented. Modification possibilities of their chemical composition, quality and productivity by use of new agriculture technique and transgenetic materials have been given. Various vegetable oils were estimated in the aspect of application as components and/or additives for fuels, lubricants, hydraulic fluids and other operational fluids.
Chemical composition and basic characteristic of many oil plants have been presented. Modification possibilities of their chemical composition, quality and productivity by use of new agriculture technique and transgenetic materials have been given. Various vegetable oils were estimated in the aspect of application as components and/or additives for fuels, lubricants, hydraulic and other operational fluids.
Chemical composition and basic characteristics of many oil plants have been presented. Modification possibilities of their chemical composition, quality and productivity by use of new agriculture technique and transgenetic materials have been given. Varoius vegetable oils were estimated in the aspect of application as components and/or additives for fuels, lubricants, hydraulic and other operational fluids.
The principles of spectrophotoacoustic methods PAS have been described. Examples of test result obtained by the author and possible applications for physical and chemical tests as well for typical as non-conventional tests also for diagnostic of technical equipment, testing of operational fluids and for control of chemical processes have been presented.
Functions of magnetic fluids in micro- and macroscopic scale, their composition and physicochemical - magnetorheological properties in relation to present and future applications have been described. Control possibilities of the rheological characteristics by use of permanent magnetic field in comparison to typical mechanical properties of these fluids i.e. vibration dumping, friction and elasticity have been presented. Role of magnetic fluids in automatic control of some equipment parameters has been described.
Application of magnetic fluids and also examples of machines and equipment have been described. The fluids can be used for reduction of friction, improvement of sealing, lubrication, and vibration dumping. Some others application have been suggested.
Application of magnetic fluids and also examples of machines and equipment have been described. The fluids can be used for reduction of friction, improvement of sealing, lubrication, and vibration dumping. Some others applications have been suggested.
Badania reologiczne ujawniły nienewtonowskie właściwości oksypochodnych oleju rzepakowego, dimeru i estolidu kwasu oleinowego oraz ich estrów: reostabilność i reoniestabilność, tiksotropię i antytiksotropię, plastyczność oraz lepkosprężystość. Zmiany lepkości przemijającej (do~90%) w zależności od prędkości ścinania (f do 2 ź 105s-1) i temperatury (-4 do 60°C) oraz energii aktywacji lepkiego płynięcia (3 do 19 kcal mol-1) i stopnia asocjacji (10(7) do 1017) oraz moduły sprężystości i czasy relaksacji (100 do 1600 Pa, 10(2 do7) s(-1) były zależne od stopnia polarności związku: maksymalne dla dimeru, pośrednie dla estolidu, minimalne dla ich estrów.
EN
Rheology research of the rapeseed oil oxyderivates and estolides as well as their esters disclosed: rheounstability and rheostability, thixotropy and antithixotropy, plnticity and viscoelasticity. Changes of the temporary viscosity (up to 90%) depending on the rates (gamma up to 2 ź 10(5)s(-1)), temperatures (- 4 to 60°C) and the activation energy of viscous flowing (3 do 19 kcal/mol) and the association degree's (to t to 10(17)) as well a, the elasticity coefficients and the relaxation times (100 to 1600 Pa, 10(2) to 10(7)s(-1)) were dependent on the polarity degree: maximal for dimer, the average for estolide and least for their esters.
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Przedstawiono wybrane zagadnienia reologii cieczy roboczych, modele fenomenologiczne nienewtonowskich cieczy magnetoreologicznych. Złożona, nieliniowa reologia tych cieczy implikuje: teoretyczne i użytkowe wskazania, możliwości oraz celowość projektowania, wykorzystywania ze zwróceniem uwagi na efekty towarzyszące w warunkach pracy urządzeń mechanicznych. Omówiono związki ze strukturami fizykochemicznymi, szerzej możliwości wykorzystania reostabilnych i reoniestabilnych, magnetoreologicznych cieczy plastycznolepkich oraz zastosowania ich modeli reologicznych do urządzeń mechanicznych.
EN
We present selected issues on the rheology of power fluids, phenomenological models of non-newtonian magnetorheologic liquids complex, non-linear rheology of these liquids implies: recommendation for application, possibilities of design and usage with particular attention paid to side, effects in working conditions of the mechanical equipment. Relations were diseased with physicochemical structures and possibilities of application of rheosunstable and rheostable, magnetorheological viscoplastk liquids and their rheological models in mechanical equipment.
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Przeprowadzone przez autorów badania porównawcze cieczy magnetycznych, (MR), modelowych krajowych oraz zagranicznych, wykazały zbliżone ich właściwości magnetoreologiczne Podano metody badań właściwości reologicznych i magnetoreologicznych. Przy nieobecności stałego pola magnetycznego przebiegi krzywych płynięcia MR były chakterystyczne dla nienewtonowskich płynów pseudoplastycznych: okresowe wzrosty, do 250% (antytiksotropia) i/lub spadki lepkości, do 80% (tiksotropia),już przy niewielkich prędkościach ścinania do 100 s(-1). W obecności pola ujawniały właściwości plastycznolepkie, charakterystyczne dla cieczy Binghama, wykazywały: zbliżone naprężenia graniczne, także duże spadki lepkości, do 90%, i nieliniowe charakterystyki płynięcia zależne od prędkości ścinania. Stabilność sedymentacyjna cieczy krajowej sięgała 120, zagranicznej 50 godz., bez spadku naprężenia granicznego.
EN
The authors performed comparative studies of magnetic liquids their home made models and the liquids produced abroad and found that their magnetorheological properties were described. The flow curves of the MR liquids, without magnetic field were typical for nonnewtonian, pseudoplastic fluids: periodic raises, up to 250% (antithixotropy), or/and falls up to 80% (thixotropy), of the viscosity, already of mades shear rate up to 100 (s-1). Some viscoplastic properties, typical for the Bingham liquids appeared without magnetic field. The exhibited similar yield stress and substantial falls of the viscosity, up to 90%, and nonlinear characteristics of flow, depending on the shear rate. Sedimentation stability of the home made liquid was 120 h and the foreign liquid 50 h, with no yield stress decrease.
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