Indian Journal of Pure and Applied Physics

 

 

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 ISSN: 0019-5596

CODEN: IJOPAU 44 (9) 713- 794

VOLUME  44

NUMBER 10

OCTOBER  2006

 

                                                                     

[This special issue is based on the papers presented at the Third National Conference on Thermophysical Properties held at International Centre Goa, Goa during January 19-20, 2005]

 

 

 

CONTENTS

 

Evaluation of thermal conductivity of ablative material

N K Sundaresan*, A Ambirajan, A Ramasamy, P P Gupta & D R Bhandari

719

Combined SANS and SAXS in studies of nanoparticles with core-shell structure

P S Goyal & V K Aswal*

724

Optical and structural properties of CdS thick film

D Patidar*, S Kumar, R Sharma, N S Saxena, Kananbala Sharma & T P Sharma

729

Molecular diffusion and confinement effect: Neutron scattering study

R Mukhopadhyay* & S Mitra

732

Effect of substrate temperature on properties of spray deposited semiconducting CdIn2S4 thin films

R R Sawant* & C H Bhosale

741

Thermal conduction and diffusion through polyester composites

Rajni Agarwal*, N S Saxena, Kanan Bala Sharma, S Thomas & Laly A Pothan

746

Effect of annealing time on thermally stimulated current in kidney stone samples

M S Gaur*, Karuna Gaur, P K Khare & Ranjit Singh

751

Thermal and doping effect on photovoltaic behaviour of H-treated (n)ZnO/(p)CdTe heterojunctions

G Wary*, T Kachary & A Rahman

754

Simultaneous measurement of thermal conductivity and diffusivity of Se85Cd15-xZnx system at room temperature

V Kishore, R Sharma & N S Saxena*

759

Positron lifetime study in FeCl3 doped polysulphone polymer

Balram Tripathi, R K Mangal, Sanjay Wate, J K Vijayavargiya, V Kulshrestha, K Awasthi,
M Singh & Y K Vijay*

763

Temperature dependence of conductivity in polyaniline-metal halide composites

N Jain*, D Patidar, N S Saxena & Kananbala Sharma

767

Magnetic study of nanoparticles of Mg0.95Mn0.05Fe2O4 spinel ferrite

S K Sharma, S N Dolia, Ravi Kumar, M Knobel, V V Siva Kumar & M Singh*

771

Synthesis, X-ray diffraction and optical band gap study of nanoparticles of NiFe2O4

S N Dolia*, Rakesh Sharma, M P Sharma & N S Saxena

774

Structural studies of synthesis of CdSe from Cd/Se bilayer

A R Chauhan, A Mahadkar, D Gaikwad & A P Patel*

777

Electrical measurements of Se85-xTe15Sbx glasses

Vibhav K Saraswat*, K Singh & N S Saxena

782

Measurement of thermal transport and optical properties of conducting polyaniline

G P Joshi*, N S Saxena, T P Sharma & S C K Mishra

786

___________

*The corresponding author has been indicated by (*) mark in case of papers with more than one author.

 

 

 

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 719-723

 

Evaluation of thermal conductivity of ablative material

N K Sundaresan, A Ambirajan, A Ramasamy, P P Gupta & D R Bhandari

Thermal Systems Group, ISRO Satellite Centre, Bangalore 560 017

Received 4 October 2005; accepted 12 July 2006

Ablatives are very often used in the Thermal Protection System of re-entry spacecraft. Their thermal conductivity will play an important role in determining the temperatures of components and payloads during the on-orbit and re-entry phases on the mission. A series of calorimetric tests were conducted on these materials to ascertain their thermal conductivity. A description of the experiments and the results of analyses of the experimental temperature data from the ablatives are presented in this paper. Three-dimensional mathematical model of the experiment was developed and analysed. The thermal conductivity of two ablative samples is determined by manually minimising the root sum of squares error (RSSE) between experimental and numerical data. The results obtained using this technique are compared with the results of a one-dimensional analysis.

Keywords: Thermal conductivity, Ablative material, Re-entry spacecraft

IPC Code: G01N25/18

 

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 724-728

 

 

Combined SANS and SAXS in studies of nanoparticles with core-shell structure

 

P S Goyal & V K Aswal*

UGC-DAE CSR, Mumbai Centre (*Solid State Physics Division), Bhabha Atomic Research Centre, Mumbai 400 085

Received 4 October 2005; revised 20 March 2006; accepted 7 August 2006

Small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS) are essentially diffraction experiments involving small (~1) scattering angles. Unlike conventional diffraction experiments (XRD or neutron diffraction) where one examines the specimen with an atomic resolution (~0.2 nm), SANS/SAXS are used to investigate structures on a length scale of ~10 nm. Hence, SANS / SAXS are ideal techniques for studying the sizes and shapes of nanoparticles. At times, because of differences in contrast for neutrons and X-rays, a combined SANS and SAXS study provides information about the core and the shell structure of nanoparticles. This paper gives an introduction to the techniques of SANS and SAXS and their applications in material science. Recent results on study of core-shell structure of a micelle (nanoparticle of organic material) are presented.

 

Keywords: Neutron scattering, Nanoparticles, Core-shell structure, Neutron diffraction

IPC Code: H01F41/30

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 729-731

Optical and structural properties of CdS thick film

 

D Patidar, S Kumar*, R Sharma, N S Saxena, Kananbala Sharma & T P Sharma

Semiconductor and Polymer Science Laboratory, 5-6, Vigyan Bhawan, Department of Physics,
University of Rajasthan, Jaipur 302 004, Rajasthan

*Department of Physics, CCS University, Meerut 250 004

Received 4 October 2005; revised 19 April 2006; accepted 3 August 2006

Cadmium sulphide film has been prepared in open-air atmosphere by sintering technique-using ZnCl2 as an adhesive source and glycol as a binder. The reflection spectra of covered sintered film of CdS are recorded by a spectrophotometer at room temperature in the wavelength range 300-700 nm. From reflection spectra, energy band gap has been determined. It is found that energy band gap of this film is 2.57 eV, which is the energy band gap of Cd0..8Zn0..2S. This is suggestive of the fact that Cd0.8Zn0.2S is a wide band gap semiconducting material. X-ray diffraction patterns also confirm the formation of Cd0.8Zn0.2S.

Keywords: Sintering technique, Reflection spectra, Energy band gap

IPC Code: B82B

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 732-740

Molecular diffusion and confinement effect: Neutron scattering study

R Mukhopadhyay & S Mitra

Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085

Received 4 October 2005; accepted 3 July 2006

Confined fluids generally have properties different from those of adsorbed layer or bulk phases. Diffusion, translational or rotational, is altered significantly on confinement. The molecular dynamics and its effect due to confinement in various environments as studied by Quasi-elastic Neutron Scattering (QENS) technique have been reported. QENS offers a unique possibility of analyzing spatial dimensions of atomic or molecular processes in their development over time. It is found that dynamics of a fluid confined in porous medium depending on the nature of the medium and interaction, can have a variety of modifications. The diffusivity of guest molecules embedded in zeolite or molecular sieves depends very much on the combination of the guest and host structures, shape and specific interactions.

Keywords: Molecular diffusion, Neutron scattering, Zeolites, Quasi-elastic neutron scattering

IPC Code: G21K1/00, G01N21/47

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 741-745

Effect of substrate temperature on properties of spray deposited semiconducting CdIn2S4 thin films

 

R R Sawant & C H Bhosale

Electrochemical Materials Laboratory, Department of Physics, Shivaji University, Kolhapur 416 004

Received 4 October 2005; revised 28 July 2006; accepted 14 August 2006

Spray pyrolysis is one of the most convenient, economical, inexpensive and simple methods for depositing large area semiconducting thin films. Semiconducting CdIn2S4 thin films have been deposited onto the amorphous and FTO coated glass substrates by varying substrate temperatures from 300, at the interval of 25 to 375C. The optimized deposition temperature is around 350C. The films have been characterized for their crystalline structure, photoelectrochemical (PEC) studies, energy dispersive analysis by X-rays (EDAX), optical and electrical transport properties by means of X-ray diffraction and thermoelectric power (TEP) measurement techniques. The cubic nature of CdIn2S4 thin films has been confirmed from XRD analysis. The PEC characterization shows that both short circuit current (Isc) and open circuit voltage (Voc) are at their optimum values at the optimized substrate temperature of 350C and solution concentration of 0.05M. EDAX studies show that the material formed at optimized preparative parameters is almost stoichiometric. The optical absorption study reveals that CdIn2S4 is indirect band gap material having band gap energy equal to 2.22 eV, matching with single crystal value. Semiconducting nature of the films is observed from the two-probe resistivity measurement. From TEP measurement, the material has been found to exhibit n-type conductivity.

Keywords: Spray pyrolysis, CdIn2S4 thin films, XRD, EDAX, Optical and electrical properties

IPC Code: C23C 016/30

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 746-750

 

 

Thermal conduction and diffusion through polyester composites

 

Rajni Agarwal1, N S Saxena2, Kanan Bala Sharma2, S Thomas3 & Laly A Pothan4

1Department of Physics, Government College, Ajmer

2Department of Physics, University of Rajasthan, Jaipur 302 004

3School of Chemical Sciences, M.G. University, Kottaayam 686 560

4Department of Chemistry, Bishop Moore College, Mavelikara 690 110

Received 4 October 2005; revised 20 March 2006; accepted 13 April 2006

Using Transient Plane Source technique, thermal properties like thermal conductivity, thermal diffusivity and specific heat of polyester composites of banana fibers (treated and untreated) are measured simultaneously at room temperature and normal pressure. The increase in thermal conductivity is observed in some treatments. The performance of the composite depends to a large extent on the adhesion between polymer matrix and the reinforcement. This is often achieved by surface modification of the matrix or the filler. Banana fiber was modified chemically to achieve improved interfacial interaction between the fiber and the polyester matrix. Various silanes and alkali were used to modify the fiber surface. Chemical modification was found to have a profound effect on the fiber/matrix interaction which is evident from the enhanced thermal conductivity values. Of the various chemical treatments, simple alkali treatment with 1% NaOH was found to be the most effective.

Keywords: Banana fibers, Polyester composites, Thermal conductivity, Thermal diffusivity

IPC Code: G01N25/18

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 751-753

Effect of annealing time on thermally stimulated current

in kidney stone samples

 

M S Gaura, Karuna Gaurb, P K Kharec & Ranjit Singhc

aDepartment of Physics, Hindustan College of Science & Technology, Farah (Mathura) U P 281 122

bDeartment of Bioscience, R D Girls College, Bharatpur, Rajasthan

cDepartment of Postgraduate Study and Research in Physics and Electronics, Rani Durgawati University, Jabalpur, MP

aE-mail: mulayamgaur@rediffmail.com

Received 4 October 2005; revised 21 March 2006; accepted 12 July 2006

An electret is a dielectric material which retains the polarization produced in it for a longer time and produces the electrostatic field without any source of voltage. The biomaterials like collagen, DNA, RNA and blood vessel walls etc possess this property. The kidney stone mainly consists of calcium oxalate and calcium phosphate, which are dipolar in nature. The pellet of the powdered kidney stone was formed in a mica window and identical aluminium electrodes were prepared. The thermal polarization was carried out by sandwiching the sample between aluminium electrodes in electrode assembly, which was kept in digital controlled oven. The observed behaviour of thermally stimulated current (TSC) peak is found to be strongly dependent on annealing time, which shows the presence of shallow and deeper traps in material. These traps are probably formed during the crystallization of substance in kidney.

Keywords: Kidney stone, Annealing time, Dipole, Shallow traps, Deeper traps

IPC Code: H01G7/02

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp 754-758

 

Thermal and doping effect on photovoltaic behaviour of H-treated (n)ZnO/(p)CdTe heterojunctions

G Wary*, T Kachary & A Rahman

*Department of Physics, Cotton College, Guwahati 781 001

Department of Physics, Gauhati University, Guwahati 781 014

*E-mail: ganesh_wary @ yahoo.co.in

Received 4 October 2005; accepted 21 June 2006

The thin film (n)ZnO/(p)CdTe heterojuctions with different doping concentrations were prepared by vacuum evaporation and their electrical and optical properties, both in dark and under illumination at room temperature as well as at elevated temperatures were studied. The structures showed change of photovoltaic (PV) effect, giving fill factor 0.59 for H-treated sample with open-circuit voltage 368 mV and short-circuit current density 76.3810-4 mA/cm2 and for untreated sample 0.46 with open-circuit voltage 250mV and short-circuit current density 57.11x104 mA/cm2 for doping concentration Na=1.301017/cm3 (4.90% Sb doped CdTe) and Nd=3.331017/cm3(4.25% Al doped ZnO). The variations of PV efficiency at room temperature with respect to these doping concentrations were shown to be the optimal value of this typical (n)ZnO/(p)CdTe junction. The fill factor has been found to increase with temperatures showing a maximum value around 343K for H-treated and 335K for untreated samples. The proper doping, annealing and hydrogenation are necessary to reduce the series resistance so as to achieve an ideal and high efficiency PV converter.

Keywords: Heterojunction, Doping, Hydrogenation, Dangling bond, Photovoltaic effect

IPC Code: H01L31/00

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 759-762

Simultaneous measurement of thermal conductivity and diffusivity
of Se85Cd15-xZnx system at room temperature

 

V Kishore, R Sharma & N S Saxena*

Semiconductor and Polymer Science Laboratory, Department of Physics, University of Rajasthan, Jaipur 302 004

E-mail: n_s_saxena@rediffmail.com*, kishore_vimal@sify.com

Received 4 October 2005; revised 19 April 2006; accepted 3 August 2006

The samples of selenium rich Se85Cd15-xZnx (x= 0, 3, 7, 11 and 15) have been prepared by slow cooling of melt technique. The pellets of the samples have been prepared at constant load of 10 ton (pressure of 866 Mpa). Measurements of effective thermal conductivity (λe) and effective thermal diffusivity (χe) of selenium rich Se85Cd15-xZnx pellets, have been carried out at room temperature using transient plane source (TPS) technique. From the measured values of λe and χe, specific heat per unit volume (Cp, derived quantity) of these samples in the composition range of investigation, have been determined. The variations of effective thermal conductivity and effective thermal diffusivity of Se85Cd15-XZnx with composition have been explained on the basis of binding energy of the alloys formed and mean free path of the phonons.

Keywords: Thermal conductivity, Thermal diffusivity, Specific heat, Mean free path

IPC Code: G01N25/18

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 763-766

 

Positron lifetime study in FeCl3 doped polysulphone polymer

Balram Tripathi, R K Mangal, Sanjay Wate*, J K Vijayavargiyac, V Kulshrestha, K Awasthi, M Singh & Y K Vijay

Department of Physics University of Rajasthan, Jaipur 302 004

*Department of Physics, Govt Arts and Science College, Ratlam 457 001

+Department of Physics, Govt College, Kota 324 001

E-mail: yk_vijay@sancharnet.in

Received 4 October 2005; revised 9 May 2006; accepted 4 August 2006

Positron lifetime measurements were performed on FeCl3 doped polysulphone (PSF) samples. As the doping % of FeCl3 increases the lifetime components τ 1 (p-Ps), and τ3 (o-Ps) decrease, while intensity component (I3) increases. It was found that the hole size and the total free volume fraction decrease with FeCl3 concentration, in polymeric membranes. There may be the cause of formation of FeCl3 clusters in polymeric chains, the FeCl3 clusters increase the cross-linking between polymeric chains. The optical measurements were also performed on these samples from which it is clear that on increasing the doping of FeCl3 , the absorption increases.

Keywords: FeCl3 doped PSF, Positron lifetime, Optical absorption, Optical microphotographs

IPC Code: G03C1/04

Indian Journal of Pure & Applied Physics

ol. 44, October 2006, pp. 767-770

 

Temperature dependence of dc conductivity in polyaniline-metal halide composites

N Jain, D Patidar, N S Saxena & Kananbala Sharma

Semiconductor and Polymer Science Laboratory, 5-6, Vigyan Bhawan, Department of Physics,
University of Rajasthan, Jaipur-302 004

E-mail: n_s_ saxena@rediffmail.com; toneerajjain@rediffmail.com

Received 4 October 2005; revised 19 April 2006; accepted 25 July 2006

Polyaniline (PANI) and its metal halide composites of trivalent metal ions of Ni and Co have been synthesized with various compositions (0, 50, 100 M%) by chemical oxidative polymerization technique with ammonium peroxydisulphate in aqueous hydrochloric acid medium. I-V characteristics of these materials at room temperature as well as function of temperature (313-393K) have been studied. The temperature and composition dependence of dc conductivity for these materials has been investigated. The dependence of conductivity on temperature is suggestive of the metallic nature of the composites and shows positive temperature coefficient of resistance. The variation of electrical conductivity in the composition shows the lowest conductivity for Co-Ni (50-50) over the values obtained for Ni (100) and Co (100) separately. This interesting result can be explained on the basis of bonding of cobalt and nickel with polyaniline matrix during their polymerization.

Keywords: Polyaniline, Metal halide composites, dc Conductivity

IPC code: G01R

 

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 771-773

Magnetic study of nanoparticles of Mg0.95Mn0.05Fe2O4 spinel ferrite

S K Sharma1, S N Dolia2, Ravi Kumar3, M Knobel4, V V Siva Kumar3 & M Singh1

1Department of Physics, H. P. University, Shimla 171 005

2Department of Physics, University of Rajathan, Jaipur 302 004

3Material Science Divisions, Nuclear Science Centre, New Delhi 110 067

4Instituto de Fisica, UNICAMP, Campinas, SP Brazil

Received 4 October 2005; revised 28 April 2006; accepted 24 July 2006

Magnetization of nanoparticles of Mg-Mn ferrite, synthesized using high energy ball milling has been studied. X-ray diffraction pattern of the particles milled for 6 h confirmed the single-phase cubic spinel structure with a lattice parameter of 8.47 . Langevin function fitting on M-H data at 300K gives a log-normal particle size distribution with median diameter of 6.4 nm and standard deviation 0.7. The isothermal dc magnetization studies have been performed using SQUID and vibrating sample magnetometer in the temperature range 5-300 K. These measurements show that the sample is superparamagnetic above the blocking temperature TB ~ 246 K. The reduction in saturation magnetization in the case of nanoparticles has been explained on the basis that the magnetic moments in the surface layers outside the core are in a state of frozen disorder.

Keywords: Nanoparticles, Spinel ferrites, Superparamagnetism

IPC Code: H01F41/30

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 774-776

Synthesis, X-ray diffraction and optical band gap study of nanoparticles
of NiFe2O4

S N Dolia, Rakesh Sharma, M P Sharma & N S Saxena

Department of Physics, University of Rajasthan, Jaipur 302 004

Received 4 October 2005; revised 4 July 2006; accepted 18 August 2006

Nanoparticles of NiFe2O4 have been synthesized by chemical co-precipitation method. X-ray diffraction pattern confirms the formation of single-phase cubic spinel structure and the lattice constant is 8.2 . The energy band gap measurements of nanoparticles of Ni ferrite in pellet form have been carried out by reflection spectra using double beam spectrophotometer. A pellet of nanoparticle ferrite was made under a load of 10 tons. From the analysis of reflection spectra, nanocrystalline Ni ferrite have been found to have energy band gap of 2.5 eV at room temperature.

Keywords: Nanoparticles, Spinel ferrites, Optical band gap, Reflection spectra

IPC Code: H01F 41/30

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp 777-781

 

Structural studies of synthesis of CdSe from Cd/Se bilayer

A R Chauhana, A Mahadkarb, D Gaikwadc & A P Pateld

aN G Acharya & D K Marathe College of Arts, Science and Commerce, Chembur, Mumbai 400 071

bTata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005

cD G Ruparel College, Matunga Road, Mumbai 400 016

dDepartment of Physics, University of Mumbai, Vidyanagari, Mumbai 400 098

Received 4 October 2005; revised 10 July 2006; accepted 7 August 2006

Cadmium and selenium bilayer have successfully been made by a vacuum evaporation technique on cleaned glass substrates under the vacuum of the order of 10-5mbar. The samples of different thicknesses were prepared by varying Cd:Se ratio as 1:1, 1:1.5,1:2. Rapid thermal annealing (RTA) of some bilayers have been carried out at different temperatures in nitrogen ambient. XRD measurements were made for structural analysis on these as-deposited and annealed samples. RTA studies could show the formation of cadmium selenide at the interface after annealing. XRF measurements were carried out for elemental analysis of these bilayers. XRF studies reveal that the films are found to be cadmium rich at room temperature. The results of CdSe formed from Cd/Se bilayer by RTA are compared with annealed sample.

Keywords: CdSe films, Wrutzite structure, Rapid thermal annealing

IPC Code: C30B

Indian Journal of Pure & Applied Physics

ol. 44, October 2006, pp. 782-785

 

Electrical measurements of Se85-xTe15Sbx glasses

Vibhav K Saraswat, K Singha & N S Saxena*

Semiconductor & Polymer Science Laboratory, 5-6, Vigyan Bhawan, University of Rajasthan, Jaipur 302 004

aDepartment of Physics, Banaras Hindu University, Varanasi

E-mail: n_s_saxena@rediffmail.com, vibhu_saraswat@sify.com

Received 4 October 2005; revised 7 August 2006; accepted 18 August 2006

Temperature dependence of I-V characteristics and dc conductivity of Se85-xTe15Sbx (where x= 2, 4, 6, 8 and 10) glasses in the form of thin pellets has been studied. The pellets have been prepared from the ingots of glasses in the powder form. It is quite evident from I-V characteristics that the glass containing 4 at wt % of Sb allow maximum current to pass through itself as compared to its other counterparts of the series. The linear relationship between ln (I) and V1/2 strongly suggests the type of conduction as the Poole-Frenkel. The deviation from ohmic behaviour at lower voltages towards the non-ohmic behaviour at higher voltages is due to the additional thermal effects at higher temperatures induced in the sample. The electrical conductivity of these samples for the above-mentioned compositions using their I-V characteristics has been determined. The variations of electrical conductivity with composition at all temperatures show that Se81Te15Sb4 glass has the maximum conductivity. This variation is explained using the bonding between Se and Sb at different compositions. Hence, the composition Se81Te15Sb4 is more chemically ordered and electrically conducting as compared to other members of the series.

Keywords: Glass, Critical composition, Bulk, Se-Sb bonding, Poole-Frenkel conduction mechanism

IPC Code: G01R

Indian Journal of Pure & Applied Physics

Vol. 44, October 2006, pp. 786-790

Measurement of thermal transport and optical properties of conducting polyaniline

 

G P Joshi, N S Saxena, T P Sharma & S C K Mishra*

Condensed Matter Physics Laboratory, Department of Physics, University of Rajasthan, Jaipur 302 004

*National Physical Laboratory, Dr K S Krishnan Road, New Delhi 110 012

Received 4 October 2005; accepted 10 July 2006

Measurements of effective thermal conductivity (λe) and effective thermal diffusivity (χe) of twin pellets of conducting polyaniline, prepared under a load of 5 ton were carried out from room temperature to 170C at normal pressure using transient plane source (TPS) technique. The values of λe and χe by the use of an empirical relation at various fixed temperature in the above mentioned range have been calculated. The calculated values are in good agreement with the experimental results over the entire range of temperatures of investigation. Besides, the optical band gap of the sample is determined using reflection spectra in the wavelength region 300-800 nm. From the analysis of reflection spectra, polyaniline is found to have energy band gap 3.1 eV. The results indicate that band gap values are dependent on annealing temperatures of the samples and λe and χe vary with annealing temperature in the range from room temperature to 170C. The effective thermal conductivity and effective thermal diffusivity are maximum at about 100C, whereas the optical band gap is minimum for the sample annealed at 100C as compared to other annealing temperatures.

Keywords: Polyaniline, Effective thermal conductivity, Effective thermal diffusivity, Transient plane source technique

IPC Code: G01N25/18