An International Research Journal

AJP Vol 10 No 3 2001


SSN : 0971 - 3093

Vol  10, No 3, July - September, 2001

Asian Journal of Physics

Vol 10, No 3 (2001) 303-454

(An International Quarterly Research Journal of Physics)
(A Non-Profitable Registered Publication)



Quantum mechanics on a lattice

F T Lee                                                                                                                                                                                                        303


Monitoring of ozone, water vapour etc during the voyage to Antarctica

S L Jain                                                                                                                                                                                                        315


Investigations on atmospheric humidity profile at varying oxygen levels with a laser based monitoring system

D Das, G A Ahmad, G K D Mazumdar and A Choudhury                                                                                                                          323


Experimental study of 2D turbulence in soap films

K Pal and S Chopra                                                                                                                                                                                     331


The electronic absorption spectra of four disubstituted phenols

R Kanna Rao, A Srinivasa Rao and D V Krishna Rao                                                                                                                                337


Study of microstrip antennas using different materials

S N Mulgi, R M Vani, P V Hunagund and Sara Fatima Farida                                                                                                                  355


Lattice dynamics of TAC and HFC using three-body force shell model

S Mohan and K Sonamuthu                                                                                                                                                                         359


Phase transitions in solid solutions of alloy semiconductors : Ga1-x, InxSb and Ga1-x InxP

Sadhna Singh                                                                                                                                                                                               363


Latitudinal dependence of solar wind speed and the sunspot cycle

T E Girish and G Gopkumar .                                                                                                                                                                     369


A non linear impurity in two-dimensional systems

R S Roy                                                                                                                                                                                                        375


Comparative study of Forbush decrease with geomagnetic storm sudden commencement

P L Verma and S K Nigam                                                                                                                                                                          379


High frequency dielectric behaviour of erbium substituted Ni-Zn ferrites

K Vijaya Kumar and D Ravinder                                                                                                                                                                391


Relationship among various interplanetary indices during maximum and minimum solar activity

G N Singh and Pankaj Kumar Shrivastava                                                                                                                                                397


A relation between cosmic rays and Dst field

M Lal and Pankaj K Srivastava                                                                                                                                                                  403


Studies on coronal mass ejections classified according to their speeds

T K Das and MK Ghosh                                                                                                                                                                             409


Influence of pressure on cosmic ray intensity at neutron monitor energies.

G.N Singh and Pankaj Kumar Srivastava                                                                                                                                                  417


On the crystallographic aspects of some naturally occurring simple and furano coumarins

Rajnikant, V K Gupta, Dinesh and Mousmi Bhat                                                                                                                                      421


Single crystal growth and X-ray crystallograhphic analysis of some 4, 4'-substituted biphenyls

Rajnikant, V K Gupta, A Kumar, R Gupta, A Kumar, Dinesh and Ashu Sawhney                                                                                     431


 Conformational analysis of some steroidal molecules

Rajnikant, V K Gupta, Dinesh and Mousmi Bhat                                                                                                                                      439


Thermal and FTIR spectroscopic studies of aspirin single crystal

Sanjay P Vachhani, R M Dabhi and M J Joshi                                                                                                                                          447

Asian Journal of Physics                                                                                                                   Vol 10, No 3 (2001)323-330


Investigations on atmospheric humidity profile at varying oxygen levels with

a laser based monitoring system


D Das1, G A Ahmed2, G K D Mazumder3 and A Choudhury4

1Department of Physics, North Gauhati College, 781031, Assam, India

2Department of Physics, Tezpur University 784028, Assam, India.

3USIC, Gauhati University, 781014, Assam, India.

4Department of Physics, Tezpur University, 784028, Assam, India;


A laser based Air Quality Monitoring system was designed and fabricated in an attempt to synthesize design principles of a nephelometer and a transmissiometer and monitor specific constituents of the atmosphere. Essentially in the system light from a He-Ne laser source passes through a simulation chamber and the extinction and scattering is monitored by a set of phototransistor based detectors. The signals from the detectors are digitized and interfaced to a personal computer, where a data acquisition software "moniotors" and records the data which is subsequently analyzed using spreadsheet programs. This paper reports the design aspects of the fabricated instrument and gives the findings of investigations done on atmospheric humidity at varying oxygen levels. ©Anita Publications. All rights reserved.




1. Ahmed G A, Mazumder G K D, Choudhary A, J Instrument Sot India, 26 (1996) 734.

2. Pritchard B S. Elliott W G, J Opt Soc Am, 50 (1960) 191.

3. Jonasz M. Appl Opt, 29, (1990) 64.

4. Hinkley E D, Laser monitoring of the atmosphere, (Springer - Verlag, Berlin), 1976, p 62.

[Received : 12.3.2001]



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