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The modern laterite gold deposits in southern China, which belong to reworked laterite deposits, can be further divided into three subclasses and seven types. Their geological features, ore-forming conditions and regularities are discussed. A geologic-geochemical metallogenic model for laterite gold deposits has been established.

Humidity detection has been widely used in a variety of fields. A humidity sensor with high sensitivity is reported in this paper. A surface acoustic wave resonator (SAWR) with high resonance frequency was fabricated as a basic sensitive component. Various nanotechnologies were used to improve the sensor's performance. A multi-walled carbon nanotube/Nafion (MWCNT/Nafion) composite material was prepared as humidity-sensitive films, deposited on the surface of an SAWR by the electrospinning method. The electrospun MWCNT/Nafion nanofiber films showed a three-dimensional (3D) porous structure, which was profitable for improving the sensor's performance. The new nano-water-channel model of Nafion was also applied in the humidity sensing process. Compared to other research, the present sensor showed excellent sensitivity (above 400 kHz/% relative humidity (RH) in the range from 10% RH to 80% RH), good linearity (R(2) > 0.98) and a short response time (∼3 s@63%).

This paper describes the production of an artificial hair cell receptor based on aligned micro/nano polyvinylidene fluoride (PVDF) fibers. Suspended aligned micro/nano fiber arrays were successfully produced on an insulator film by a novel method called thermo-direct drawing procedure. Using this method, aligned micro/nano-size PVDF fibers are obtained. Some key problems such as the fabrication of the electrodes on a single fiber along fiber drawing direction and poling of micro/nano fibers to endow them with good piezoeffective activity have been presented. Comparative experiments show that the artificial hair cell receptor has reliable response with good sensibility under pressure stimulation if a standard pressure sensor is taken as a reference. The preliminary validation experiments show the novel artificial receptor is a promising technique in the detection of the flow medium speed and vibration.