Ch Devi Lal University

Sirsa, India

Ch Devi Lal University

Sirsa, India
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Kumar H.,Ch Devi Lal University | Neetu,Ch Devi Lal University
Research Journal of Chemistry and Environment | Year: 2017

Carbon allotropes like graphene and carbon nanotubes, have been incorporated in amperometric sensors for sensitive and selective detection of environment pollutants. An electrochemical biosensor based on graphene powder working electrode whose properties are modified with conducting polymer polyaniline (PANI) was specially designed and fabricated for electrochemical detection of environment pollutant like hydrazine. Electrochemical characterization was carried out by using cyclic voltammetry, ampereometry, linear sweep voltammetry and optical microscopy. The developed amperometric sensor displays good electrochemical-activity towards the detection of hydrazine. Storage and stability conditions of the working electrode were also tested. Fabricated non-enzymatic amperometric sensor was successfully used for the precise, sensitive and specific detection of hydrazine present as an environment pollutant. © 2017, International Congress of Chemistry and Environment. All rights reserved.


Kumar H.,Ch Devi Lal University | Rani R.,Ch Devi Lal University
Science Progress | Year: 2013

This review discusses current development in biosensors for the detection of biological warfare agents (BWAs). BWAs include bacteria, virus and toxins that are added deliberately into air, water and food to spread terrorism and cause disease or death. The rapid and unambiguous detection and identification of BWAs with early warning signals for detecting possible biological attack is a major challenge for government agencies particularly military and health. The detection devices - biosensors - can be classified (according to their physicochemical transducers) into four types:. electrochemical, nucleic acid, optical and piezoelectric. Advantages and limitations of biosensors are discussed in this review followed by an assessment of the current state of development of different types of biosensors. The research and development in biosensors for biological warfare agent detection is of great interest for the public as well as for governments.


Rachna,Ch Devi Lal University | Aghamkar P.,Ch Devi Lal University
Optical Materials | Year: 2013

Nanocrystalline yttrium oxide-silica has been successfully synthesized by wet chemical process. Y (NO3)3·4H2O and TEOS were used as precursors and obtained powdered form of Y2O 3:SiO2 binary oxide. The powdered samples were annealed at 250 C and 500 C temperature and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, Photoluminescence (PL) and Transmission electron microscopy (TEM). The XRD results predicted that the as-prepared sample has mixed phase of Y(NO 3)(OH)3 and Si(OH)2. However, cubic yttrium oxide phase alone is found for annealed sample with average grain size ∼8 nm at 500 C (6 h). Sample analyzed by FTIR and TEM confirmed the grain size dependency on sintering temperature. From the UV-Vis spectra, it is found that the position of the absorption peak is shifted towards the lower wavelength side with sintering temperature. In the PL spectra, the broad emission band is centered at 585 nm.


Ahlawat R.,Ch Devi Lal University
Ceramics International | Year: 2015

Y2O3:SiO2 powder was synthesized by a sol-gel method, using hydrous yttrium nitrate and hydrous silicon oxide as precursors and HCl as a catalyst. The dried samples were submitted to multi-step annealing schedule in air without applying pressure. A simple four-step annealing schedule with a final stage of about 900 °C for 6.0 h was followed. The samples of Y2O3:SiO2 nanocomposites were obtained with well defined size and shape. Structural changes of the nanocomposites were investigated by XRD, FTIR and TEM. Multi-step annealing scheme with different ramp rates and incubation times allows recovery-relaxation processes within the boundaries and leading to a concomitant linear increase of crystallite size and densification. Almost fully dense quasi-spherical cubic-yttria nanopowder has been demonstrated with an average grain size distribution of 10-40 nm; can be uniformly dispersed in silica matrix. © 2015 Elsevier Ltd. and Techna Group S.r.l. All rights reserved.


Siwach P.,Ch Devi Lal University | Gill A.R.,Ch Devi Lal University
Physiology and Molecular Biology of Plants | Year: 2011

Ficus religiosa (Pipal) is a long-lived valuable multipurpose forest tree. The tree is exploited because of its religious, ornamental and medicinal value and the regeneration rate in natural habitat is low. An in vitro propagation protocol has been developed from nodal segments obtained from a 45-50-year old tree. The highest bud break frequency (100 %) followed by maximum number of multiple shoots (13.9) as well as length (2.47 cm) were obtained on Woody Plant medium (WPM) supplemented with 1.0 mg/l BAP along with 0.5 mg/l IAA. Two modifications in this medium resulted in enhanced shoot regeneration-one with 200 mg/l glutamine + 150 mg/l ADS (called as MM-1) giving 32.5 shoots per nodal explant while another modification-with 200 mg/l glutamine + 150 mg/l ADS + 100 mg/l phloroglucinol (called as MM-2) giving 35.65 shoots per explant. These two media were used for sub-culturing of shoots for 4 months. The rate of shoot multiplication was same during the first three sub-cultures on MM-1 and the shoots regenerated were healthy, afterwards shoot multiplication declined. While on MM-2, shoot multiplication declined after first sub-culture and shoots underwent the problem of early leaf fall. Rooting was best induced in micro-shoots excised from proliferated shoot cultures on semi-solid as well as liquid WPM modified with 2.0 mg/l IBA and 0.5 mg/l IAA. The in vitro-raised plantlets were potted and acclimatized under culture room conditions for 25-30 days before transfer to soil conditions, where the established plants showed more than 90 % survival. © 2011 Prof. H.S. Srivastava Foundation for Science and Society.


In this paper, the reflection and refraction of longitudinal wave from a plane surface separating a micropolar viscoelastic solid half space and a fluid saturated incompressible half space is studied. A longitudinal wave (P-wave) impinges obliquely at the interface. Amplitude ratios for various reflected and transmitted waves have been obtained. Then these amplitude ratios have been computed numerically for a specific model and results thus obtained are shown graphically with angle of incidence of incident wave. It is found that these amplitude ratios depend on angle of incidence of the incident wave as well as on the properties of media. A particular case when longitudinal wave reflects at free surface of micropolar viscoelastic solid has been deduced and discussed. From the present investigation, a special case when fluid saturated porous half space reduces to empty porous solid has also been deduced and discussed with the help of graphs. © 2014 IAU, Arak Branch.


Singh R.M.,Ch Devi Lal University
Pramana - Journal of Physics | Year: 2014

Making use of an ansatz for the eigenfunction, we investigate closed-form solutions of the Schrödinger equation for an even power complex deictic potential and its variant in one dimension. For this purpose, extended complex phase-space approach is utilized and nature of the eigenvalue and the corresponding eigenfunction is determined by the analyticity property of the eigenfunction. The imaginary part of the energy eigenvalue exists only if the potential parameters are complex, whereas it reduces to zero for real coupling parameters and the result coincides with those derived from the invariance of Hamiltonian under PT operations. Thus, a non-Hermitian Hamiltonian possesses real eigenvalue, if it is PT-symmetric. © Indian Academy of Sciences.


Ahlawat R.,Ch Devi Lal University
International Journal of Applied Ceramic Technology | Year: 2015

Gd(NO3)3.6H2O and TEOS were used as precursors and obtained Gd2O3:SiO2 ceramic powder having different concentration of Gd2O3 as 2.2, 2.8, 3.4, and 4.0 wt % using solgel process. The powdered samples were annealed at 500°C and 900°C temperatures and characterized by XRD, FTIR, SEM, and TEM. In X-ray diffraction, cubic phase of Gadolinium oxide is reported only for the annealed samples having higher concentration (3.4 & 4.0 wt %) of Gd2O3. SEM and TEM results further confirm that the surface morphology of the microstructures depend on the temperature and concentration. © 2014 The American Ceramic Society.


Ahlawat R.,Ch Devi Lal University
International Journal of Applied Ceramic Technology | Year: 2015

Gd(NO3)3·6H2O and TEOS were used as precursors and obtained powdered form of Gd2O3:SiO2 nanocomposite. The as-prepared sample was annealed at 773 K and 1173 K and characterized by XRD, TEM, UV-Vis spectra, and PL. The average nanocrystallite size was found of the order of ~27 nm using well-known Debye-Scherer's equation. From the UV-Vis spectra, it was shown that the position of absorption peak has been shifted toward the higher wavelength side with temperature. In the PL spectra, the broad emission band has been observed at 583 nm along with weak bands at 516, 526, and 556 nm. © 2015 The American Ceramic Society.


Ahlawat R.,Ch Devi Lal University
Journal of Alloys and Compounds | Year: 2015

SiO2:RE2O3 [RE = Y, Gd] powder were prepared by wet chemical technique and the prepared binary oxides annealed at 500 °C and 900 °C. The crystalline structure, phase transformation, and surface morphologies of as-prepared and annealed samples were investigated by XRD and TEM. The normal transmission was measured using FTIR spectroscopy. Optical properties have been studied with UV-Vis spectroscopy and PL study. XRD results shows that the as prepared samples of SiO2:RE2O3 [RE = Y, Gd] powder has mixed phases of RE(NO3)3 and Si(OH)3. However, cubic rare earth oxide phase alone is found for annealed samples. The strain values are calculated from W-H plot for annealed samples. TEM micrograph shows that the samples are composed of individual spherical nanocrystallites at 500 °C and aggregated nanocrystallites at 900 °C. From the UV-Vis spectra, it is found that the position of the absorption peak is shifted toward the higher wavelength side when annealing temperature is increased. In the PL spectra, the broad emission bands are observed between 570-600 nm and the presence of O-Si-O (silica) and metal oxide is confirmed by FTIR spectra. © 2015 Elsevier B.V.

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