National University of Singapore

Hui Tong Chua

Kim Choon Ng

Bidyut Baran Saha

Anutosh Chakraborty

Takao Kashiwagi

Tuck Wah Ng

Atsushi Akisawa

Jeffrey M Gordon

Osami Sasaki

Abdul Malek

The present invention provides a hybrid optical and interferometric atomic force microscope system () for monitoring a cantilever probe (). A light source () provides a light beam which is focussed on the back of the cantilever probe (). The light reflected off the probe is split into two beams of different path lengths and are recombined to form an interference beam (). This interference beam () is passed through a grating () having substantially the same period and orientation as the interference beam pattern. The light transmitted through the grating () illuminates a photodetector () to give a signal according to the intensity of the light falling on the photodetector. The photodetector output signal is sent to a positioning system (), which in turn gives a signal to the piezoelectric system () so that the probe () follows the sample () surface. This signal is integrated as a function of position across the scanned area to represent a characteristic of the sample surface. An array of light beams, cantilever probes and photodetectors are also provided, and a plurality of characteristics may be obtained by performing a single scan on the sample surface. Actuators are also provided on the grating () and mirrors in the interferometer () to modulate the fringes of the interference beam () and cancel out noise in the microscope system ().

High sensitivity scanning probe system

A regenerative adsorption process and a multi-reactor regenerative adsorption chiller assembly including a condenser adapted to receive a coolant from a source; an evaporator connected to the condenser to provide a refrigerant circuit; a plurality of reactors, each being able to operate in adsorption and desorption modes and having a coolant inlet to directly or indirectly receive coolant when operating in adsorption mode before, after or simultaneous with the condenser, and a waste heat inlet for directly or indirectly receiving waste heat from a waste heat source when operating in desorption mode; and control means for controlling said plurality of reactors such that each reactor alternately operates in adsorption and desorption modes for substantially identical time intervals, and such that each reactor has an equal chance of being the first reactor to receive the coolant when operating in adsorption mode, and the waste heat from the waste heat source when operating in desorption mode.

Regenerative adsorption process and multi-reactor regenerative adsorption chiller

A novel modular and miniature chiller is proposed that symbiotically combines absorption and thermoelectric cooling devices. The seemingly low efficiency of each cycle individually is overcome by an amalgamation with the other. This electro-adsorption chiller incorporates solely existing technologies. It can attain large cooling densities at high efficiency, yet is free of moving parts and comprises harmless materials. The governing physical processes are primarily surface rather than bulk effects, or involve electron rather than fluid flow. This insensitivity to scale creates promising applications in areas ranging from cooling personal computers and other micro-electronic appliances, to automotive and room air-conditioning.

Electro-adsorption chiller: a miniaturized cooling cycle with applications from microelectronics to conventional air-conditioning

Growing community of inventors

Singapore, Singapore

Hui Tong Chua