A highly sensitive atomic force microscope for linear measurements of molecular forces in liquids

Karakose, M
Oral, Ahmet
We describe a highly improved atomic force microscope for quantitative nanomechanical measurements in liquids. The main feature of this microscope is a modified fiber interferometer mounted on a five axis inertial slider which provides a deflection sensitivity that is significantly better than conventional laser deflection based systems. The measured low noise floor of 572.0 fm/root Hz provides excellent cantilever amplitude resolution. This allows us to operate the instrument far below resonance at extremely small cantilever amplitudes of less than 1 angstrom. Thus linear measurements of nanomechanical properties of liquid systems can be performed. In particular, we present measurements of solvation forces in confined octamethylcyclotetrasiloxane and water with amplitudes smaller than the size of the respective molecules. In general, the development of the instrument is important in the context of quantitative nanomechanical measurements in liquid environments.


A new method to measure viscosity and intrinsic sound velocity of liquids using impedance tube principles at sonic frequencies
Mert, Behiç; Campanella, OH (AIP Publishing, 2004-08-01)
The attenuation of the sound energy produced by a liquid contained in a cylindrical tube (wave guide) depends on the liquid's viscosity, sound frequency, tube wall thickness, and tube material. By measuring the acoustic impedance of plane sound waves in a cylindrical wave guide, one can obtain the liquid's viscosity. Impedance measurements can also provide sound velocity in the liquid medium as another important physical characteristic. In this study a method using the impedance tube technique is presented....
Wide-field turbulence imaging with beam emission spectroscopy
McKee, G. R.; Fonck, R. J.; Shafer, M. W.; Uzun Kaymak, İlker Ümit; Yan, Z. (AIP Publishing, 2010-10-01)
Imaging of the size, shape, time-averaged, and time-resolved dynamics of long-wavelength density turbulence structures is accomplished with an expanded, high-sensitivity, wide-field beam emission spectroscopy (BES) diagnostic on DIII-D. A 64-channel BES system is configured with an 8 X 8 grid of discrete channels that image an approximately 7 X 9 cm region at the outboard midplane. The grid covers multiple correlation lengths and each channel shape matches the measured radial-poloidal correlation length asy...
An instrument for the high temperature measurement of the Seebeck coefficient and electrical resistivity
GÜNEŞ, Murat; Parlak, Mehmet; Ozenbas, Macit (IOP Publishing, 2014-05-01)
A system for the simultaneous measurement of thermoelectric power and resistivity of one and/ or two samples over a temperature range of 300-1000 K in a vacuum chamber is designed and implemented. A sample probe is developed to provide its easy mounting and usage. In addition, two samples can be measured at the same time. Measurement accuracy has been enhanced by beadless thermocouples and micro-heaters that are specifically designed in order to minimize the 'cold-finger effect' and to eliminate some possib...
A mean-field model for the phase diagram of liquid crystals
Tublek, A; Yurtseven, Hasan Hamit; Salihoglu, S (Informa UK Limited, 1998-01-01)
In this study we have developed a mean-field model to obtain the phase diagram for a mixture of liquid crystals. Our mean-field model gives the phase diagram of the nematic, smectic A and smectic C phases near the NAC point. We have fitted our model to the experimentally observed data. From this fitting, we conclude that our mean-field model explains correctly the experimentally observed behavior of a mixed liquid crystalline system near the NAC point.
An optical fiber radiation sensor for remote detection of radiological materials
Klein, DM; Yukihara, EG; Bulur, Enver; Durham, JS; Akselrod, MS; McKeever, SWS (Institute of Electrical and Electronics Engineers (IEEE), 2005-08-01)
This paper demonstrates the feasibility of a portable radiation sensor system that uses the pulsed optically stimulated luminescence technique to remotely interrogate an aluminum oxide (Al2O3:C) radiation sensor via an optical fiber. The objective is to develop a system for applications requiring simple and inexpensive sensors for widespread monitoring of ionizing radiation levels, which can be remotely interrogated at regular periods with little or no human intervention and are easy to install, operate, an...
Citation Formats
S. PATİL, G. MATEİ, H. DONG, P. HOFFMANN, M. Karakose, and A. Oral, “A highly sensitive atomic force microscope for linear measurements of molecular forces in liquids,” REVIEW OF SCIENTIFIC INSTRUMENTS, pp. 0–0, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39875.