Formation of stable nanobubbles in aqueous solutions of water-soluble organic molecules is a spontaneous process. Using a combination of laser light scattering (LLS) and zeta-potential measurements, we investigated the effects of salt concentration and pH on their stability in alpha-cyclodextrin (alpha-CD) aqueous solutions. Our results reveal that the nanobubbles are unstable in solution with ...

Cement has been used for decades in the industry to serve various important functions inside oil and gas wells. Due complications variations geological technical conditions of a well, cement compositions are designed utilized different world regions. Many hydrocarbon reservoirs covered by thick salt formations, which considered problematic costly be drilled cemented. slurry, as water based solu...

This paper discusses the problems of impedance sensors in their application. Four case studies of industrial sensors are presented and show how a systematic approach can reduce the effects of undesired physical influences. It is shown that in a first case of ideal environmental conditions, with capacitive sensors even with simple interface electronics a very high precision can be obtained. A se...

Aims. The recent Cassini discovery of water vapor plumes ejected from the south pole of the Saturnian satellite, Enceladus, presents a unique window of opportunity for the detection of extant life in our solar system. Methods. With its significant geothermal energy source propelling these plumes >80 km from the surface of the moon and the ensuing large temperature gradient with the surrounding ...

UV-vis reflection spectroscopy has been used for proving in situ the organization of pure viologen and hybrid viologen tetracyanoquinodimethanide monolayers at the air-water interface. Other more classical measurements concerning Langmuir monolayers, including surface pressure-area and surface potential-area isotherms, are also provided. The organization of the viologen in the Langmuir monolaye...

The addition of low concentrations of the hydrotropic salt p-toluidine hydrochloride (PTHC) to solutions of the anionic surfactant sodium dodecyl sulfate (SDS) promotes the transition from spherical to rodlike micelles. NMR measurements confirm that the hydrotrope adsorbs at the micelle-water interface, thereby screening electrostatic repulsions between the surfactant headgroups. The sphere-to-...

controlled drainage is one of the strategies to reduce negative environmental effects in conventional drainage systems. this study examines the effect of controlled drainage on quality and quantity of drainage water, specifically amounts of salt and nitrate in drainage water, and nitrate uptake by maize (sc 704) with sandy loam soil texture in karaj. the experiment was performed as a randomized...

The protein transduction domain of HIV-1 TAT, TAT(48-60), is an efficient cell-penetrating peptide (CPP) that diffuses across the lipid membranes of cells despite eight cationic Arg and Lys residues. To understand its mechanism of membrane translocation against the free energy barrier, we have conducted solid-state NMR experiments to determine the site-specific conformation, dynamics, and lipid...