Gold/polyvinyl alcohol nano-composites with two different concentrations of gold (~1.0 wt% and ~2.0 wt% respectively) were prepared via in-situ reduction of gold salt by employing hydrazine hydrate as a reducing agent. The optical absorption spectra of nanocomposites reveal the shift in the surface plasmon resonance band from 525 nm to 560 nm with increase in gold concentration. The obtained nanocomposites were doped with meta-nitroaniline (m-NA). The m-NA doping resulted into slight blue shift of the surface plasmon resonance band of gold along with appearance of a new band at 356 nm due to m-NA. The nanocomposites were further characterised using X-ray diffraction, Scanning electron microscopy and transmission electron microscopy were used to study particulate properties. It is observed that the particle size of gold varies with gold concentration. In this report for the first time we report a humidity sensor based on these nanocomposites, having response time of 50 s (20-95% RH) and recovery time of around 3 min (95%-20%RH) on fibre optical waveguide, in the range of 20-100% RH. The optimum concentration of gold is found to be 2.0 wt %, which showed higher performance for humidity sensing. The sensing performance was found to be enhanced after m-NA doping.
- Inderscience Publishers
- Optical humidity sensor based on m-nitroaniline doped ...
Safe Landings Whatever the Weather: Lufft Sensors on Airports
Pilots, air traffic controllers and airport operators do their best to make air travel safer and more efficient. Sometimes, however, flight security depends on external factors we can hardly influence. This especially refers to risky weather conditions: Strong winds, icy cold or strong precipitation can have serious consequences. On average, 23% of all aircraft accidents and 68% of canceled flights in 2015 are attributable to adverse weather conditions (source: FAA). How dangerous weather conditions are, is...
Tech Tip: Deploying Sea-Bird CTD in Ice
Large numbers of Sea-Bird conductivity instruments have been used in Arctic and Antarctic programs. Special accommodation to keep temperature, conductivity, oxygen, and optical sensors at or above 0° C is advised. Often, the CTD is brought inside protective doors between casts to achieve this. Conductivity Cell When freezing is possible, we recommend that the conductivity sensor be stored dry. Remove larger droplets of water by blowing through the cell. Do not use compressed air, which typically contains...
Optical encoders and LiDAR scanning
Overview Modern technology is taken for granted; a driver only needs to type a destination into a SATNAV system and step-by-step instructions, journey distance and duration, driving conditions and hazards, as well as alternative routes, instantly appear. In order to work, highly accurate and up-to-date maps are required of an entire country`s road network. This non-trivial task becomes significantly more complex for the world`s largest countries. China, as the world`s most populous country and...
Where do you find the latest meteo technologies at one place?
Sustainability is the main theme of both the Meteorological Technology World Expo and the CIMO Teco (Technical Conference on Meteorological and Environmental Instruments and Methods of Observation) held in Madrid from September 27 until 29, 2016. Therefore it’s the optimal platform to present one of our latest environmental sensor developments to a broad public: the WS3000 weather sensor. Besides, you have the change to take a look at a product premiere and other proven high-tech meteo sensors from Lufft. Th...
Cloud simulation instead of data cloud: the CHM Simulator
MARWIS as all-rounder: the new CHM Simulator is able to simulate clouds with the help of the sensor which is normally used for traffic meteorology applications. The name of the simulator equipment refers to the cloud height sensor CHM 15k, which can measure up to 15 km into the height and detects different types of clouds. The CHM Simulator is an absolute novelty for the efficient and prompt maintenance of the cloud height sensor CHM 15k. From now on, you can check the measurement system’s performance at...