EXPERIMENTAL FACILITIES AVAILABLE WITH R & D GROUP PHYSICS DEPARTMENT
Bought under DST project DST-SERB – SR/FTP/PS-055/2010 entitled “Development of X-ray imaging plate based on filmless radiography- Optimization of grain size, morphology and image contrast of BaFBr:Eu2+ X-ray storage Phosphor”.
JobinYvonFluromax 4 (Made in USA) has single – grating excitation and emission spectrometers with 1,200 groves mm-1 with following specifications: Resolution- 0.2 nm, Accuracy – 0.5 nm, Speed- 150 nm/s, Excitation and Emission slits – 1.25 mm. The standard signal detector is a photon counting detector made of Hamamatsu Photonics R928P photomultiplier tube. The response of detectors range from 200-1050 nm with dark counts < 1000 counts per sec (cps). Photon counting linear range is 0-2 million cps. And the working range is up to 2 million cps.In Fluoromax 4 spectrofluorometer, the standard 150W xenon arc lamp is used. The xenon lamp spectrum exhibits a characteristic peak around 467 nm.
Application – Powder and liquid samples which emit light (photoluminescence) under light illumination can be analysed using the above instrument Fight on RHS show excitation and emission spectra of Zn2SiO4:Mn green emitting phospohor under UV light illumination
Bought under BRNS project– 2013/36/47-BRNS/2422 entitled “Development of a stable RPL/TL phosphor with linear response for radiation dosimetry in high dose region”.
Thermoluminescence (TL) Reader Type TL1009I designed and offered by Nucleonix Systems, Hyderabad is a versatile controller based unit, facilitating the user to subject the TL sample under study to the desired heating profile, to record the digitized TL glow curve. This unit records the data in 150 channels, temp, TL intensity & Run time values. Entire electronics including PMT, HV bias, Temperature controller circuit, Heater transformer, heater strip, sample drawer assembly, data acquisition electronics is all integrated into a single enclosure.
Thermocouple sensor (Cr-Al spot –welded to heater strip) is used to monitor sample temperature. A continuously adjustable HV (0-1200V) at 1.0 mA is generated by HV circuits. We can select desired HV from front panel depending on the intensity of TL signal so ther instrument current does not saturate.. Kanthal strip (72% Fe, 23% Al and 2% Cr or Nichrome) is used as a heating element. It has a circular depression of 14mm to hold discs and powder samples. From room temperature up to 500°C, in linear, plateau heating (One / Two / Three) modes of heating can be programmed. Heater strip can be programmed to heat the sample from 0.5°C/sec upto 40°C/sec.
Application –Radiation dosimetry – Thermoluminescent powder or crystalline samples which emit light whose intensity is proportional to radiation dose it received can be analyzed with the above instrument
Figure on RHS show TL glow curves of CaCO3:Dy after x-irradiation.
Bought under BRNS project– 2013/36/47-BRNS/2422 entitled “Development of a stable RPL/TL phosphor with linear response for radiation dosimetry in high dose region”.
It is a closed box for safety with an opening for sample insertion. It contains a 254nm short UV Lamp, 360 nm long UV Lamp and Visible Hg white Light.
Application – A quick method to check if a substance is fluorescent and under what excitation wavelength.It is used routinelyto check if a suspected currency note is counterfeit or genuine since it contains fluorescence markers.
4. Dry Grinder (used for grinding red chilli) for Recycling PTFE Scrap
Capacity : 3HP motor
Bought with personal funding.After powdering the PTFE scrap it is ram extruded to make recycled rods shown above. The technology is developed for the first time in India. It is available for technology transfer
5. SEMCO Muffle Furnace
Max temperature: 1100oC
First furnace bought under SEC funding in 2008.This furnace is the main working horse used for synthesizing several luminescent phosphors even today.
Figure on the RHS show the recently developed SrS:Eu2+red emitting PL phosphor used for white LED applications. Under room light, the phosphor is orange in color and under 450 nm LED light, it looks magenta in color. SrS:Eu2+ emission occurs in red region (~600 nm) . Together with incident blue light (450 nm) the color looks magenta. Along with green emitting YAG:Ce (RBG) the phosphor exhibits white emission.
Max temperature: 1200oC
Bought under Mining project – Me4-14/7/2017-Metal IV/Record Cell – 26-3-2018.Entitled “Processing of Sea sand for construction and other purposes”
Sea sand mixture before sintering (left), sintered sand on removal from furnace (middle) and on cooling (right)
The two major issues of the application of sea sand for construction, namely salt content and fine size could be overcome by sintering it at a high temperature with suitable additives using the above furnace. A rotary gas fired furnace capable of producing large quantity of processed sea sand is under construction.
This technology is also ready for technology transfer
Max temperature: 350oC
Bought under TEPP – DSIR DSIR/TePP/309/2008 entitled “Development of Filler grade PTFE powder and Recycling of PTFE scrap materials”.
The above air oven is used for drying wet samples
Bought under TEPP – DSIR DSIR/TePP/309/2008 entitled “Development of Filler grade PTFE powder and Recycling of PTFE scrap materials”.
Top left – Vanjax hydraulic press with suitable hand pump, pressure gauge (0-3000 psi pressure range )& hose
Photographs of Vanjax hydraulic press (top left), various sizes of dye and plunger (top right),LiF:Mg pellets (bottom left)andpellets made fromRepro+ virgin mixtures (brown colored) and virgin PTFE powder (white colored)(bottom right).
Capacity : 12 ton
This press is used for making cold pressed pellets using suitable dye and plunger which are subsequently sintered at high temperatures. All inorganic and metallic powder samples can be pelletized wit this hand operated pressure.
Display – 0.0000 g, Capacity : 220 g
Min: 0.1 mg, Max: 220 g, error: 0.001 g, d: 0.1 mg
Bought under BRNS project– 2013/36/47-BRNS/2422 entitled “Development of a stable RPL/TL phosphor with linear response for radiation dosimetry in high dose region”.
All samples weighing below 220 g can be weighed with an accuracy of 0.1 mg
