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Polycrystalline Zn

Being a clean energy carrier, hydrogen is considered as fuel for future. It is the lightest and most abundant element in the universe. Magnesium has shown promise for onboard hydrogen storage as it has enormous hydrogen content. Further, uptake of molecular hydrogen in modified Mg is a prospect for efficient hydrogen storage. Hydrogen uptake capacity of Mg can be improved with loading of transition metals. In this work effect of the ball-milling and different wt% of Fe on structural and morphological properties of Mg powder was conducted. Pristine Mg powder was milled for 12 h and then milled for a further 2 h after adding x wt% of Fe (x = 5,10 & 20). In this manner Mg - x wt% Fe (x = 5,10 & 20) nanocomposites were prepared. Structural, morphological and elemental analysis of these samples is completed by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM) and energy-dispersive X-ray spectroscopy (EDXS) respectively. Results indicate that the Mg with an effective additive could be used as hydrogen storage material systems.

The present study was conducted to assess the effectiveness of structured teaching programme on neonatal resuscitation among the staff nurses. An experimental design was chosen with pre-test and post-test of experimental and control group. The sample size was 60 registered staff nurses divided into two groups as 30 in experimental and 30 in control group. The tools used for conducting the study included demographic variables, self-structured questioner to assess knowledge of experimental and control group. The experimental group was given structured teaching programme and the control group was used for comparison only. The data were analyzed with the help of descriptive and inferential statistics. The study clearly shows that there was a significant gain in knowledge of staff nurses in experimental group with structured teaching programme which emphasizes neonatal resuscitation by the staff nurses. Therefore, the staff nurses can be benefited with structured teaching programme to improve knowledge on neonatal resuscitation.

Cutting of sheet material is considered as an important process due to its relevance among products of everyday life as well as well as in high strength application in aircrafts, ships, cars, structures, military ,naval purpose etc. Based on recent study it is found that many high strength sheet martial are cut using CO2 laser and it is important to know how the cutting is affecting the material properties and which parameters are responsible for such change. As steel is the most common type of material used in the manufacturing industry so the research is based on the different grade of steels and the effect on those when processed using CO2 laser beam cutting. The various parameters and their effects are shown in the given study which is analyzed by different researchers along the course of time. The material, thickness and different optimization techniques by different researchers is also shown

Metal matrix composites (MMCs) possess significantly improved properties including high specific strength, damping capacity, specific modulus and good wear resistance compared to unreinforced alloys. There has been an increasing interest in composites containing low density and cost reinforcements also their ability to be produced by conventional methods adds to the advantage. Aluminium matrix can be strengthened by reinforcing it with hard ceramic particles like SiC, Al2O3 and B4C, etc. This paper presents an overview of the effect of on B4C addition as reinforcement in aluminium alloy highlighting their merits and demerits. Major issues like, fiber-matrix bonding, agglomerating phenomenon and the problems related to distribution of particles is discussed in this paper. Effect of B4C reinforcement on AMCs mechanical properties like tensile strength, strain, hardness, wear and fatigue is also discussed in detail.

The present paper deals with the study of thermo-mechanical performance of PVC/ZnO nanocomposites. The samples have been prepared by solution casting technique with different (0, 2, 4, 6 and 8) wt. % of ZnO nanoparticles in poly (vinyl chloride) (PVC) matrix and structurally characterized through scanning electron microscopy. In thermo-mechanical analysis, dynamic mechanical analyzer gives the information about storage modulus and phase transition temperature (Tg). From these viscosities, profile at elevated temperature and activation energy of phase transition can be evaluated. This study reveals that dispersion of nano-ZnO significantly altered the thermo-mechanical properties of neat PVC but the effect is composition-dependent.

The ZnSe-rGO nanocomposite with various stacking of rGO by simple solvothermal route was reported along with its characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), Raman and photoluminescence spectroscopy. SEM as well as TEM pictures predict that ZnSe nanoparticles were embedded on the graphene sheets with average particle size 15 nm and are well decorated on the surface of rGO sheets. Photocatalytic activity's improvement for degradation of MB by ZnSe-rGO nanocomposites was observed, which is described in term of interaction between ZnSe nanoparticles and rGO sheets and charge carrier sepatation. It is also reflected in photoluminescence and Raman studies. This plays a crucial role in minimizing electron-hole recombination through transfer of electron from ZnSe to rGO.

In the present study ZnSe quantum dots (QDs) were synthesized by chemical co-precipitation method using mercaptoethanol as the capping agent. These nanostructures were characterized for structure and surface morphology by using X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectrometry respectively. The average size of ZnSe quantum dots from XRD and HRTEM is found to be 4–5 nm having cubic crystalline phase. Effect of annealing temperature, which were determined as phase transformation temperatures (299 and 426 °C) using differential scanning calorimetry has been investigated for structural and thermal stability of QDs. The XRD of annealed samples at temperatures 325 and 442 °C (slightly higher than the temperatures corresponding to two crystallization peaks in the DSC scan) have been carried out to find structural changes corresponding to these annealing temperatures. Sample annealed at 325 °C showed no change in the phase except improvement in intensity of peaks (crystallinity) whereas sample annealed at 442 °C showed transitions from cubic phase of ZnSe to ZnO and orthorhombic phases of ZnSeO4, ZnSeO3. Emergence of ZnO peaks in the XRD pattern of annealed samples have been further verified by Raman spectroscopy of the annealed samples. Besides this crystallization kinetics of ZnSe quantum dots has been employed to determine activation energies of these transitions due to oxidation by employing Kissinger, Augis Bennett and Ozawa’s models. Higher activation energy of crystallization corresponding to first crystallization peak shows that the cubic phase is more thermally stable.

Electrical conductivity of chalcogenide glassy system Ge30−xSe70Sbx (x = 10, 15, 20 and 25) prepared by melt quenching has been determined at different temperatures in bulk through the I–V characteristic curves. It is quite evident from results that Poole–Frenkel conduction mechanisms hold good for conduction in these glasses in a given temperature range. The variation in electrical conductivity with composition was attributed to the Se–Sb bond concentration in the Se–Ge–Sb system. Results indicated that Ge5Se70Sb25 showed the minimum resistance. In view of this the composition Ge5Se70Sb25 may be coined as ‘critical composition’ in the proposed series. Also the activation energies of conduction of these glassy alloys have been calculated in higher and lower temperature range using the Arrhenius equation.

CdSe quantum dots (QDs) having size 3–5 nm have been synthesized by chemical co-precipitation method in mixed amorphous and cubic phase. These QDs have been characterized by using X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared (FTIR) spectrometry. Cubic phase is confirmed by XRD and amorphous phase have been found using differential scanning calorimetry (DSC). The thermal analysis carried out by using DSC at different heating rates shows endothermic and exothermic peaks at different temperatures corresponding to their glass transition and different crystalline phases. The cubic phase of the crystalline CdSe obtained at 261 °C in the DSC scan of as prepared sample start transforming to stable hexagonal phase of CdSe corresponding to second crystallization peak 317 °C in DSC thermogram. Differential thermal analysis (DTA) and thermogravimetric analysis (TGA) have also been used to determine the crystallization temperature (257 °C) and weight loss in the temperature range 220–267 °C. Activation energies corresponding to two exothermic peaks (cubic and hexagonal phase) have been determined by employing different theoretical models. Lower activation energy of the hexagonal phase corresponding to second exothermic peak obtained at higher temperature in the DSC thermogram shows the higher thermal stability of this phase and could be employed for preparing a material to improve the performance of memory devices, solar cells etc.

Thermal transport properties like effective thermal conductivity ( λ e ) and effective thermal diffusivity ( k e ) of Ge–Se–Sb chalcogenide glassy alloys were measured simultaneously using transient plane source (TPS) technique from room temperature to 260 °C at normal pressure. Twin pellets of the sample, prepared under a load of 5 ton, were used for these measurements. In the studied temperature range, both λ e and k e initially remain almost constant from room temperature to 160 °C and then increase to maxima with further increase of temperature, and thereafter decrease with increasing temperature. This variation has been explained phenomenologically on the basis of variation of phonon mean free path with temperature. An effort has been made to predict this behavior by an empirical relation obtained from polynomial fit of the experimental data. The calculated values of λ e and k e are in good agreement with the experimental results over the entire range of temperatures under investigation.

Measurements of thermal transport properties such as effective thermal conductivity (λ e) and effective thermal diffusivity (k e) of Ge30−xSe70Snx (x = 8, 11, 14, 17, and 20) chalcogenide glasses have been made using transient plane source technique in temperature range from room temperature to 300 °C. Both effective thermal conductivity (λ e) and effective thermal diffusivity (k e) are almost constant in the temperature range from room temperature to 240 °C. Beyond 240 °C, both λ e and k e increase with the increase in temperature and show maxima at a particular temperature which is a characteristic temperature for a given material. For further increase in temperature, both λ e and k e decrease slowly. Addition of Sn concentration in the glass increases the value of λ e and k e over the entire range of temperature under investigation for all five samples. Here, an effort has also been made to predict the values of both λ e and k e by using empirical relationships.

Current-voltage characteristics and DC electrical conductivity were studied for Ge30-xSe70Snx (x = 8, 11, 14, 17 and 20) glassy thin pellets of diameter 12mm and thickness 1mm prepared under a constant load of 5 tons using a well-known melt quenching technique in bulk as a function of composition. The I-V characteristics were recorded at room temperature as well as elevated temperatures up to 300?C. The experimental data suggests that glass containing 20 at.% of Sn has the minimum resistance allowing maximum current through the sample as compared to other counterparts of the series. Therefore, DC conductivity is found to increase with increasing Sn concentration. Composition dependence of DC conductivity is discussed in terms of the bonding between Se and Sn. Plots between ln I and V1/2 provide linear relationship for both low and high voltage range. These results have been explained through the Pool-Frenkel mechanism. The I-V characteristics show ohmic behaviour in the low voltage range and this behaviour turns to non-ohmic from ohmic in the higher voltage range due to voltage induced temperature effects.

Measurements of the effective thermal conductivity $$(\lambda _{\mathrm{e}})$$ and effective thermal diffusivity $$(k_{\mathrm{e}})$$ of $$\hbox {Ge}_{30-x}\hbox {Se}_{70}\hbox {Sb}_{x}\,(x = (10, 15, 20$$ , and 25) at. wt.%) chalcogenide glasses have been carried out in the temperature range from room temperature to above the glass transition temperature using the transient plane source technique. In the heating process, variations of $$\lambda _{\mathrm{e}}$$ and $$k_{\mathrm{e}}$$ are observed. Both quantities remain approximately constant in the temperature range from room temperature to $$160\,^{\circ }$$ C, beyond which a linear increase is observed and they reach a maximum in the vicinity of a critical temperature called the glass transition temperature $$(T_{\mathrm{g}})$$ . It is interesting to note that $$\lambda _{\mathrm{e}}$$ and $$k_{\mathrm{e}}$$ decrease above the glass transition temperature of the glasses. Such a type of behavior can be explained on the basis of structural changes occurring in $$\hbox {Ge}_{30-x}\hbox {Se}_{70}\hbox {Sb}_{x}\,(x = (10, 15, 20$$ , and 25) at. wt.%) chalcogenide glasses. Results also indicate that both $$\lambda _{\mathrm{e}}$$ and $$k_{\mathrm{e}}$$ increase with increasing weight percentage of Sb. This is because of an increase of the weak bond density in the glassy system with the addition of Sb.

The effect of dispersion of CdS nano-filler particles in respective PS/PVC and PS/PMMA polymer blend matrices on the effective thermal conductivity has been studied through Hot Disk Thermal Constant Analyzer based on transient plane source (TPS) technique. The thick film samples have been prepared by dispersing nano-filler particles of CdS (6 wt%) in respective PS/PVC and PS/PMMA binary blend matrices. The nanocomposite nature of prepared samples ascertained through small angle X-ray scattering (SAXS) as well as transmission electron microscopy (TEM) measurements. It is observed that at room temperature nano CdS dispersed polymeric blend samples offer higher effective thermal conductivity.

The kinetics of crystallization of Ge30-xSe70Sbx (x=15, 20, 25) chalcogenide glasses has been investigated using differential scanning calorimetery at different heating rates under non-isothermal conditions. The kinetic analysis of crystallization has been discussed using different theoretical approaches such as Ozawa model, Augis and Bennet model, Matusita model and Gao-Wang model. It is evident from this study that the activation energy of crystallization Ec is composition dependent. The activation energy decreases with increasing Sb content due to the increasing of rate of crystallization. The minimum value of the frequency factor Ko, which is defined as the number of attempts made by the nuclei per second to overcome the energy barrier, confirms the fact that glass is more stable. It has been found that Ge15Se70Sb15 glass is more stable compared to the other compositions.

CdSe-rGO nanohybrids with different weight content of rGO were synthesized using hydrothermal route and characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared (FTIR), Raman, absorption and photoluminescence (PL) spectroscopies. The XRD shows that CdSe nanoparticles have wurtzite hexagonal structure. The FTIR and Raman spectra reveal that CdSe nanoparticles are grown on rGO sheets. Results of SEM and TEM indicate that hybrid structure with low rGO loading shows homogeneous dispersion of CdSe on rGO sheets, while high loading leads to the agglomeration of CdSe nanoparticles. UV–vis absorption spectra indicates that CdSe-rGO nanohybrids enhance absorbance in UV as well as visible region, while intensity of PL decreases as compared to CdSe. An improvement in photo-degradation of MB by CdSe-rGO nanohybrids is observed, which is described in term of interaction between CdSe nanoparticles and rGO. This plays a crucial role to minimize recombination of charge carriers through transfer of electron from CdSe to rGO.

CdS/PS and ZnS/PS nanocomposites have been prepared by solution casting method with different wt% of cadmium sulphide (CdS) and zinc sulphide (ZnS) nanoparticles and characterized through X-ray diffraction and transmission electron microscope measurements. The effective thermal conductivity of polymer nanocomposites has been measured by transient plane source method over the temperature range from room to 150 °C. The experimental results showed that the thermal conductivity has been found to increase up to 4 wt% of CdS/ZnS nanoparticles and then decrease for 6 and 8 wt% of nanoparticles.

PVC/CdS nanocomposites have been prepared by solution casting method taking 2, 4, 6 and 8 wt% of CdS nanoparticles. PVC/CdS nanocomposites were characterized through TEM measurement. The measurement of effective thermal conductivity of PVC/CdS nanocomposites has also been done using transient plane source (TPS) method. The effects of concentration of CdS nanoparticles and temperature on the effective thermal conductivity of polymer PVC/CdS nanocomposites have been studied. The variation of effective thermal conductivity with the concentration of filler particles and temperature has also been discussed in terms of dispersion of filler particles into polymer matrix and phonon scattering mechanism, respectively.

Kinetic studies of two-phase transformations i.e. glass transition and crystallization for GexSe70Sb30-x (x = 5, 10, 15, 20) glasses have been performed using differential scanning calorimetry (DSC) at different heating rates under non-isothermal condition. The glass transition and crystallization regions have been investigated in terms of their characteristic temperatures i.e. glass transition temperature Tg and crystallization temperature Tc and activation energy. The activation energies of glass transition and crystallization have been calculated by employing peak shift method of Kissinger and isoconversional methods. Activation energies have been found to be dependent on the composition. The thermal stabili- ty is determined from the temperature difference ΔT = Tc — Tg where Tc and Tg are the onset crystallization and glass transition temperature respectively. It has been found that Ge15Se70Sb15 glass is thermally more stable as compared to the other members of the series.

The cadmium sulfide/polystyrene (CdS/PS) nanocomposites with concentration (0, 2, 4, 6, and 8) wt% of CdS nanoparticles were prepared by solution casting method and characterized through fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) measurements. The particle size of nanoparticles is found to be around 15 nm. Glass transition and mechanical behavior of CdS/PS nanocomposites were investigated using dynamic mechanical analyzer (DMA). The mechanical properties such as Young's modulus and tensile strength were determined at room, as well as at elevated temperatures through their stress–strain curves. The result shows that glass transition temperature (Tg) is shifted toward the higher temperature after the addition of CdS nanoparticles. The mechanical properties increased at low wt% loading of CdS nanoparticles and decreased for higher wt% loading of CdS nanoparticles. It was also found that mechanical properties decline with increase in the temperature. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers

The high quality Cu 3 Se 2 phase of copper selenide nanoparticles was synthesized through the solution-phase chemical reaction between copper and selenium. In this synthesis process, hydrazine hydrate acts as reducing agent whereas ethylene glycol controls the nucleation and growth of particles. An effort has been made to explain the growth mechanism to form copper selenide nanoparticles through the coordination of selenium to the Cu 2+ complexes with OH groups of ethylene glycol. Result indicates the formation of Cu 3 Se 2 single phase nanoparticles. The particles with the average particle size 25 nm are spherical in shape having tetragonal structure. The particles are well crystallized having 94% degree of crystallinity. An effort has also been made to determine the energy band gap of copper selenide nanoparticles through the absorption spectra.

In this article, ZnS nanoparticles were prepared by wet chemical precipitation method using zinc sulphate (ZnSO4), sodium sulphide (Na2S) and thio-glycerol. These nanoparticles were characterized through X-ray diffraction (XRD) and transmission electron microscope (TEM) measurements. The solution-based processing was used to prepare Poly methyl methacrylate (PMMA) nanocomposites with different weight percents (0, 2, 4, 6 and 8) of ZnS nanoparticles. The obtained ZnS/PMMA nanocomposites were characterized through XRD, scanning electron microscope and TEM measurements. The dynamic mechanical analyzer was used to obtain the storage modulus and glass transition temperature (T g) of the nanocomposites. The apparent activation energy of the glass transition region was also determined using the Vogel–Fulcher–Tammann equation. The results indicated that the thermal stability of ZnS/PMMA nanocomposites was higher than PMMA and 6 wt. % of ZnS nanoparticles in PMMA matrix showed the maximum activation energy, which ...

This article deals with the study of some mechanical properties of ZnS/poly(methyl methacrylate) nanocomposites prepared by solution casting method. The obtained ZnS/PMMA nanocomposites have ZnS nanoparticles in (0, 2, 4, 6, and 8) wt % and characterized through X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and Fourier transform infrared (FTIR) spectroscopy measurements. Mechanical properties of ZnS/PMMA nanocomposites have been determined at different temperatures (30°C, 50°C, 70°C, and 90°C) through their stress–strain behavior using dynamic mechanical analyzer (DMA). The properties have been found to increase upto 6 wt % of ZnS nanoparticles and then decrease for 8 wt % of ZnS nanoparticles. A theoretical model has also been employed to predict the strain softening and strain hardening of the material. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

The storage modulus and glass transition temperature (T g) of CdS/PMMA nanocomposites have been evaluated as a function of concentration of CdS nanoparticles. CdS particles have been synthesised via chemical route using cadmium acetate, thiourea and dimethylformamide. The solution-based processing has been used to prepare PMMA composites with CdS nanoparticles at different filler concentration. Size and shape of CdS nanoparticles in PMMA have been determined with the help of small angle X-ray scattering and transmission electron microscope measurements. Dynamical mechanical analysis was carried out on the CdS/PMMA nanocomposites to study storage modulus and tan δ. It is observed that CdS nanoparticles enhance the storage modulus and T g for composites. The storage modulus and T g show the maximum value of 6 wt.% of CdS nanoparticles embedded PMMA composite. The results indicate that the 6 wt.% of CdS nanoparticles in PMMA matrix provides more stability to the composite over the other composites.

Nanoparticles of chemically synthesized CdS with the different weight percents (0, 2, 4, 6, and 8 wt%) have been embedded into poly(methyl methacrylate) (PMMA) by solution casting method. The obtained CdS/PMMA nanocomposites are characterized through small-angle X-ray scattering and transmission electron microscope measurements. Temperature-dependent mechanical properties of CdS/PMMA nanocomposites have been studied at different temperatures (30, 50, 70, and 90°C) using stress–strain behavior through dynamic mechanical analyzer. Results indicate that CdS nanoparticles are uniformly distributed at low weight percent, and agglomeration of particles is observed at high weight percent and all the quantities obtained from stress–strain relations, i.e., Young’s modulus, tensile strength, and fracture energy increase up to 6 wt.% of CdS nanoparticles and then decrease for further increase of weight percent of CdS nanoparticles.

CdS/PMMA nano-composites at different weight percent of CdS (0, 2, 4, 6, and 8) have been prepared using solution casting method. The obtained nano-composites are characterized through the transmission electron microscope (TEM). The differential scanning calorimetry (DSC) measurements have been done on the nano-composites at different heating rates. The peak glass transition temperature is determined using the DSC thermograms. It is found that the glass transition temperature increases with the increase of CdS content up to 6 wt% and then decreases for higher weight percent (8). It is explained on the basis of molecular motion of PMMA, which is restricted when CdS is added into PMMA. An effort is also made to study the activation energy of glass transition in the case of nano-composites of different weight percent of CdS. Variation of activation energy with CdS nano-particle concentration has also been theoretically predicted by using an empirical relation. Thermal stability of these nano-composites has been explained with the help of activation energy in the glassy region.

A systematic study has been made on the behavior of Al/n-CdS thin film junction on flexible polymer substrate (polyethylene terephthalate, PET) grown using thermal evaporation method. Temperature dependence of I-V measurements for this junction has been done which closely follow the equations of Schottky barrier junction dominated by thermionic emission mechanism. Intrinsic and contact properties such as barrier height, ideality factor and series resistance have been calculated from I-V characteristics. The barrier height of Al/n-CdS junction is found to increase with increase in temperature whereas ideality factor and series resistance decrease with increase in temperature.

Pure Polyaniline (EB) and Polyaniline doped with different protonic acids (ESs) were chemically synthesized using ammonium peroxydisulphate (APS) as an oxidant. Junctions have been prepared by evaporating chalcogenide materials (ZnSe, CdSe) on conducting polyaniline (EB & ESs) pellets using a vacuum evaporation technique. I–V characteristics of junctions have been studied at room temperature using the Keithley electrometer 6517A. I–V measurements show the rectification effect. A junction of ES[PO43−] may be preferred over the other junctions due to its low ideality factor and maximum rectification ratio.

A thin film of zinc selenide (ZnSe) was deposited onto a clean glass substrate using a vacuum evaporation technique. This thin film was characterized through X-ray diffraction, which indicated that the film was polycrystalline in nature. Absorption and transmission spectra of this thin film were recorded using a spectrophotometer. The energy band gap, refractive index and extinction coefficient were determined using these spectra. It was found that the energy band gap of ZnSe film was 2.55 eV. It was also observed that the refractive index and extinction coefficient of the film decreased with the increase of wavelength. The conductivity of this thin film was determined by current–voltage measurement using an electrometer over the temperature range from room temperature to 413 K. It was observed that conductivity increased with increase in temperature. This is explained on the basis of structural changes occurring due to the change in grain size and the increase in carrier density.

The thin films of Cd1-x Zn x S (x = 0, 0.2, 0.4, 0.6, 0.8 and 1) have been prepared by the vacuum evaporation method using a mechanically alloyed mixture of CdS and ZnS. The structural, optical and electrical properties have been investigated through the X-ray diffractometer, spectrophotometer and Keithley electrometer. The X-ray diffraction patterns of these films show that films are polycrystalline in nature having preferential orientation along the (002) plane. In the absorption spectra of these films, absorption edge shifts towards lower wavelength with the increase of Zn concentration. The energy band gap has been determined using these spectra. It is found that the energy band gap increases with increasing Zn concentration. The electrical conductivity of so prepared thin films has been determined using a I–V characteristic curve for these films. The result indicates that the electrical conductivity decreases with increasing Zn content and increases with temperature. An effort has also been made to o...

Chemical method has been used to prepare cadmium sulphide by using cadmium, hydrochloric acid and H2S. The reflection spectra of covered and uncovered sintered films of CdS have been recorded by ‘Hitachi spectrophotometer’ over the wavelength range 300–700 nm. The energy band gaps of these films have been calculated from reflection spectra. It is found that the energy band gap of both films is same as 2.41 eV. It is indicated that energy band gap of these films does not change. This value of band gap is in good agreement with the value reported by other workers. The measurement of photocurrent has also been carried out using Keithley High Resistance meter/ Electrometer. This film shows the high photosensitivity and high photocurrent decay. Thus so obtained films are suitable for fabrication of photo detectors and solar cells.

Simultaneous measurement of effective thermal conductivity ( λ e ) and effective thermal diffusivity ( χ e ) of twin pallets of Se 100− x In x ( x =0,5, 10, 15, and 20) glasses, prepared under a load of 5 tons, have been made at room temperature using the Transient Plane Source (TPS) technique. The values of λ e and χ e were found to increase initially with the increase of concentration of In in Se–In alloy and had their maximum at 10 at.wt% of indium. For indium concentration beyond 10 at.wt% of the values of effective thermal conductivity and effective thermal diffusivity decrease linearly. This is suggestive of fact that 10 at.wt% of indium can be considered as a critical composition at which the alloy becomes, chemically ordered and maximum thermally stable than other composition. Further addition of indium in selenium decreases the values of λ e and χ e . The behaviour is explained on the basis of decrease of localized states and increase in disorderness for higher composition indium.