Wyniki wyszukiwania - BazTech

1

Testing brake fluid wear processes in complex constrained conditions

Bąkowski H., Stanik Z., Kubik A.

Tribologia

|

2017

|

nr 3

21--27

EN

The study determined the effect of increased water content in a brake fluid by measuring its hydration and boiling temperature and examining the impact of brake fluid wear on the safety and reliability of a kraking system. Within the scope of work, the temperature of the brake discs was determined according to the kraking distance. An experimental bench was set up to determine the boiling point of the hydrated brake fluid. The position is designed to reflect the operating conditions of intense braking and lead to the boiling of the brake fluid. A summary of all laboratory and operating tests of the brake fluid tested allowed the minimum kraking distance to be determined after which the brake fluid of varying degrees of hydration (over various operating periods) could boil beyond the permitted boiling point.

PL

W pracy określono wpływ zwiększonej zawartości wody w płynie hamulcowym poprzez pomiar jego zawodnienia i temperatury wrzenia oraz badanie wpływu zużycia płynu hamulcowego na bezpieczeństwo i niezawodność układu hamulcowego. W ramach pracy wyznaczono temperatury tarcz hamulcowych w zależności od drogi hamowania. Skonstruowano eksperymentalne stanowisko do wyznaczenia temperatury wrzenia w zawodnionym płynie hamulcowym. Stanowisko ma za zadanie odzwierciedlić warunki eksploatacyjne panujące podczas intensywnego hamowania i prowadzące do zagotowania się płynu hamulcowego. Zestawienie wszystkich badań zarówno laboratoryjnych, jak i eksploatacyjnych badanego płynu hamulcowego pozwoliło na próbę wyznaczenia minimalnej drogi hamowania, po przekroczeniu której płyn hamulcowy o różnym stopniu zawodnienia (w różnych okresach eksploatacji) może się zagotować, przekraczając dopuszczalną temperaturę wrzenia.

2

Quantitative Modeling of Physical Properties of Crude Oil Hydrocarbons Using Volsurf+ Molecular Descriptors

Saaidpour S., Ghaderi F.

Computational Methods in Science and Technology

|

2016

|

Vol. 22, No. 3

133--141

EN

The quantitative structure-property relationship (QSPR) method is used to develop the correlation between structures of crude oil hydrocarbons and their physical properties. In this study, we used VolSurf+ descriptors for QSPR modeling of the boiling point, Henry law constant and water solubility of eighty crude oil hydrocarbons. A subset of the calculated descriptors selected using stepwise regression (SR) was used in the QSPR model development. Multivariate linear regressions (MLR) are utilized to construct the linear models. The prediction results agree well with the experimental values of these properties. The comparison results indicate the superiority of the presented models and reveal that it can be effectively used to predict the boiling point, Henry law constant and water solubility values of crude oil hydrocarbons from the molecular structures alone. The stability and predictivity of the proposed models were validated using internal validation (leave one out and leave many out) and external validation. Application of the developed models to test a set of 16 compounds demonstrates that the new models are reliable with good predictive accuracy and simple formulation.

3

Investigation of pyrolysis behavior of fenoxycarb using PY-GC-MS assisted with chemometric methods

Wang G., Hou Z., Sun Y., Liu Y., Xie B., Liu S.

Chemia Analityczna

|

2007

|

Vol. 52, No. 1

141-156

EN

Fenoxycarb is a carbamate-type insect growth regulator. To investigate its pyrolysis behavior, it was pyrolysed at 600°C, 750°C and 9QQ°C. Pyrolysate was directly subjected to GC-MS analysis. The separated components were identified using probability-based matching procedure followed by correlation of the boiling point- Lee retention index. It has been shown that (Py-GC-MS) pyrolysis assisted with chemometric methods is an effective technique for the investigation of carbamate pesticide pyrolysis, 84 components were determined in pyrolysate, which included the products of thermal decomposition of fenoxycarb, a variety of monoaromatics, polycyclic aromatic hydrocarbons, and other oxygenous or nitrogenous compounds. Determination of the components of pyrolysates may provide useful information for understanding of the pyrolysis mechanism of fenoxycarb and other carbamate pesticides.