optimization of drilling fluid parameters such as mud weight, salt concentration, and temperature is essential to alleviate instability problems during drilling through shale sections. the selection of suitable mud parameters can benefit from analyses that consider significant instability processes involved in shale-drilling–fluid interactions. this paper describes the development of analytical...

the pressure drop of refrigerant r-134a flow boiling inside a horizontal tube has been investigated experimentally. the test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. these instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. this system consisted of three electrically heated evapor...

Although the multiplication of bacteriophages (phages) has a substantial impact on the biosphere, comparatively little is known about how the external environment affects phage production. Here we report that sub-lethal concentrations of certain antibiotics can substantially stimulate the host bacterial cell’s production of some virulent phage. For example, a low dosage of cefotaxime, a cephalo...

The Wagner equation for prediction of vapor pressure has been modified in order to improve it accuracy. On the basis of this modifications, development of a new equation for prediction of vapor pressure is outlined. Examples of the use of the equation for obtaining vapor pressure for a total of 94 pure substance are given. The proposed equation combines simplicity and accuracy and performs as w...