Non-linear free vibrations and post-buckling analysis of shear flexible functionally graded beams

K. Sanjay Anandrao,R.K. Gupta,P. Ramchandran,G. Venkateswara Rao 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.3

Large amplitude free vibration and thermal post-buckling of shear flexible Functionally Graded Material (FGM) beams is studied using finite element formulation based on first order Timoshenko beam theory. Classical boundary conditions are considered. The ends are assumed to be axially immovable. The von-Karman type strain-displacement relations are used to account for geometric non-linearity. For all the boundary conditions considered, hardening type of non-linearity is observed. For large amplitude vibration of FGM beams, a comprehensive study has been carried out with various lengths to height ratios, maximum lateral amplitude to radius of gyration ratios, volume fraction exponents and boundary conditions. It is observed that, for FGM beams, the non-linear frequencies are dependent on the sign of the vibration amplitudes. For thermal post-buckling of FGM beams, the effect of shear flexibility on the structural response is discussed in detail for different volume fraction exponents, length to height ratios and boundary conditions. The effect of shear flexibility is observed to be predominant for clamped beam as compared to simply supported beam.

Studies on Milk Allantoin and Uric Acid in Relation to Feeding Regimens and Production Performance in Buffaloes

Sikka, P.,Saxena, N.K.,Gupta, R.,Sethi, R.K.,Lall, D. Asian Australasian Association of Animal Productio 2001 Animal Bioscience Vol.14 No.11

Allantoin and uric acid were estimated in milk to study the association between the levels of these purine derivatives and milk production per day under given feeding regimens. Keeping the stage of lactation, parity and initial milk yield in view thirty lactating buffaloes were randomly selected from early lactating group. All the animals were fed 30 kg green, 2 kg straw and 5 kg concentrate mixture on per animal/day basis at basal level up to 8 1 produce. 1 kg concentrate mixture, soaked cotton seed and boiled cotton seed was fed for every 2 I milk, respectively in Group I (control), Group II and Group III animals. Average milk Allantoin and Uric acid levels were $120{\pm}11.7g/ml$ and $4.03{\pm}0.63g/ml$, respectively in milk. Cotton seed feeding enhanced the milk production significantly (p<0.01) in comparison to concentrate mixture fed control group animals. A significant difference (p<0.01) in milk allantoin levels was found over the different feeding management at higher level of production group animals. Study also revealed a significant negative correlation between the milk allantoin and production per day r=-0.43 (p<0.05).

Modification of surface behaviour of Eichhornia crassipes using surface active agent: An adsorption study

Sumanjit,Seema,R.K. Mahajan,Vinod Kumar Gupta 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

Eichhornia charcoal modified with cationic surfactant is used as an adsorbent. The characterization wasdone by Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller, X-ray diffraction, scanningelectron micrograph, and point of zero charge measurements. Effect of contact time, initial dyeconcentration, adsorbent dose and temperature were studied. Experimental data were contemplated forvarious kinetic models and thermodynamic models and interpreted that adsorption followed secondorder kinetic model. Langmuir model deduced the maximum adsorption capacity as 103.2 mg g 1 at323 K. Gibbs free energy, enthalpy and entropy have been calculated and the present adsorption systemis speculated as spontaneous and endothermic in nature.

Synthesis and adsorption properties of mesoporous material for the removal of dye safranin: Kinetics, equilibrium, and thermodynamics

Sumanjit Kaur,Seema Rani,R.K. Mahajan,M. Asif,Vinod Kumar Gupta 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.22 No.-

A highly ordered large pore mesoporous adsorbent MCM-41 is synthesized and characterized by XRD,BET, FTIR and SEM. Effect of contact time, initial dye concentration, adsorbent dose, pH and temperaturewere studied for adsorption of dye safranin on MCM-41. Experimental data were investigated for variousthermodynamic models and kinetic models and corroborated that adsorption followed second orderkinetic model. Langmuir model evidenced the maximum adsorption capacity as 68.8 mg g 1 at 303 K. Thermodynamic parameters surmised that adsorption of safranin on MCM-41 is spontaneous,exothermic and feasible.

Photoluminescence, thermoluminescence and evaluation of some parameters of Dy³⁺ activated Sr₅(PO₄)₃F phosphor synthesized by sol-gel method

Gupta, K.K.,Kadam, R.M.,Dhoble, N.S.,Lochab, S.P.,Singh, V.,Dhoble, S.J. Elsevier Sequoia 2016 JOURNAL OF ALLOYS AND COMPOUNDS Vol.688 No.2

In this study, we have synthesized Dy<SUP>3+</SUP> activated Sr<SUB>5</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>F (S-FAP) phosphors by sol-gel synthesis method. The synthesized phosphors were characterized by X-ray diffraction pattern (XRD), scanning electron microscopic (SEM), photoluminescence (PL) and thermoluminescence (TL) for structural, morphological and luminescent properties. Dy<SUP>3+</SUP> activated Sr<SUB>5</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>F phosphor shows its characteristic PL emission at 481 nm and 574 nm due to <SUP>4</SUP>F<SUB>9/2</SUB> → <SUP>6</SUP>H<SUB>15/2</SUB> and <SUP>4</SUP>F<SUB>9/2</SUB> → <SUP>6</SUP>H<SUB>13/2</SUB> transitions, respectively. TL characteristics of Dy<SUP>3+</SUP> doped Sr<SUB>5</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>F phosphors were taken after irradiation by <SUP>60</SUP>Co gamma exposure. Two separate TL peaks at 126 <SUP>o</SUP>C and 279 <SUP>o</SUP>C were observed in case of Dy<SUP>3+</SUP> doped phosphor. Sr<SUB>5</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>F:Dy<SUP>3+</SUP> phosphor was irradiated within a wide range of exposure of 50 Gy to 7 kGy doses. Linearity was found up to 2 kGy and thereafter TL response saturates. Fading study was also carried out over the duration of six weeks for Sr<SUB>5</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>F phosphor. Trapping parameters were calculated using Chen's peak shape method, initial rise method and various heating rate method. Glow curve is deconvoluted using computerized glow curve deconvolution program. TL sensitivity of Sr<SUB>5</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>F:Dy<SUP>3+</SUP> phosphor is found to be less by a factor of 2.08 than commercially used CaSO<SUB>4</SUB>:Dy phosphor. In order to identify the defect centers formed upon γ-ray irradiation in Sr<SUB>5</SUB>(PO<SUB>4</SUB>)<SUB>3</SUB>F:Dy<SUP>3+</SUP> phosphor, EPR measurements were carried out on un-irradiated and irradiated phosphors.

Interactions of methylated $\beta$-cyclodextrin and hydrophobically modified alkali-soluble emulsion (HASE) polymers: a rheological study

Gupta, R.K.,Tam, K.C.,Ong, S.H.,Jenkins, R.D. The Korean Society of Rheology 2000 Korea-Australia rheology journal Vol.12 No.2

The interactions between methylated $\beta$-cyclodextrin (CD) and hydrophobically modified alkali-soluble associative polymers (HASE) were examined by a rheological technique. The effect of "capping" of hydrophobes by methylated $\beta$-cyclodextrin on the viscosity and modulus was evaluated. Model HASE polymers with $C_1$to $C_{20}$ alkyl hydrophobic groups ethoxylated with~10 moles of ethylene-oxide (EO 10) and at concentrations up to 3 wt% were examined. With the addition of methylated $\beta$-CD, the steady shear viscosity profiles shift from a Newtonian profile to one that display a shear-thinning characteristic. Significant "capping" of the hydrophobes occurs for HASE polymers with $C_{l2}$, $C_{16}$ and $C_{20}$ hydrophobes as reflected by the large reduction in the viscosity. However, the steady shear viscosity remains constant when the concentration of $\beta$-CD exceeds 1 wt%, suggesting that $\beta$-CD is not able to fully encapsulate the hydrophobes of the HASE polymer. The temperature variation plots indicate that the activation energy of the HASE-EO10-$C_{20}$ system and $\beta$-CD is dependent on the magnitude of the applied shear stress. These results further reinforce the hypothesis that $\beta$-CD is not able to completely remove all the hydrophobic associations.phobic associations.

Enhancing bio-suppression of Parthenium hysterophorus L.: Diapause in Zygogramma bicolorata Pallister and its manipulation through insulin-like peptides (ILPs)

R.K. Gupta,Salil Gupta,K. Bali,K. Srivastava 한국응용곤충학회 2010 Journal of Asia-Pacific Entomology Vol.13 No.4

In-depth investigations on diapause behaviour of Z. bicolorata revealed that the adults entered diapause at any time from August to December and that the number peaked (42.00%) during the last half of November. The percentage of adults entering diapause increased with a decrease in day length. Weight of diapausing adults was significantly higher than weight of non-diapausing adults. The percentage of adults undergoing diapause at 30 °C was significantly lower than those undergoing diapause at 15 and 25 °C. The percentage of adults burrowing increased with increasing moisture. In silty soil and soil with high organic matter, 46.7%and 49.2% of adults entered diapause, respectively, whereas in sandy soil, only 23.5% of adults entered diapause. When newly emerged beetles were exposed to 5 μg of human insulin 30/70, a significantly lower percentage of treated adults underwent diapause compared to untreated adults under both feeding and no feeding conditions. Insulin treatment also influenced the emergence period from diapause (93.92±1.73 days), percent emergence (81±1.54%) and fecundity/month (512.7±25.38 eggs) of Z. bicolorata in treated adults as compared to untreated adults (109.05±2.2, 74.00±1.82 and 438.3±19.33 eggs,respectively). However, there was no significant impact of insulin on adult longevity. These findings are of great utility in the biological suppression of Parthenium as it will enhance the effectiveness of this beetle through manipulation of diapause.

Antitumor effect of Careya arborea against Ehrlich ascites carcinoma with reference to lipid peroxidation and enzymatic and non enzymatic antioxidant system in Swiss albino mice

R Sambath Kumar,T Sivakumar,V Senthil,N Venkateswara Murthy,V Balasubramaniam,R Kanaga Sabi,R. Shanmuga Sundram,P Perumal,U K Mazumder,M Gupta 경희대학교 융합한의과학연구소 2008 Oriental Pharmacy and Experimental Medicine Vol.8 No.2

The methanol extract of stem barks of Careya arborea Roxb. (MECA) (Family- Myrtaceae) was evaluated for antitumor activity and antioxidant status against Ehrlich’s Ascites Carcinoma (EAC) bearing Swiss albino mice. After 24 h of tumor inoculation the MECA was administered at the doses of 50, 100 and 200 mg/kg body weight/mice/day for 14 days. After the last dose and 18 h fasting mice were sacrificed. The effect of MECA on the growth of transplantable murine tumor, life span of EAC bearing hosts, hematological profiles, serum and liver biochemical parameters were estimated. The MECA showed significant (P < 0.01) decrease in ascites volume, packed cell volume and viable cell count and prolonged the life span of EAC tumor bearing mice. Hematological profiles reverted to more or less normal levels in extract treated mice. The MECA also produced protective effect by decreasing the activity of serum enzymes, bilirubin and increase the protein and uric acid levels. MECA significantly (P < 0.05) decreased the levels of lipid peroxidation, while significantly (P < 0.05) increased the levels of glutathione content, vitamin C, vitamin E, superoxide dismutase and catalase CAT. The results indicate that MECA exhibited significant antitumor and antioxidant activity in EAC bearing mice. The methanol extract of stem barks of Careya arborea Roxb. (MECA) (Family- Myrtaceae) was evaluated for antitumor activity and antioxidant status against Ehrlich’s Ascites Carcinoma (EAC) bearing Swiss albino mice. After 24 h of tumor inoculation the MECA was administered at the doses of 50, 100 and 200 mg/kg body weight/mice/day for 14 days. After the last dose and 18 h fasting mice were sacrificed. The effect of MECA on the growth of transplantable murine tumor, life span of EAC bearing hosts, hematological profiles, serum and liver biochemical parameters were estimated. The MECA showed significant (P < 0.01) decrease in ascites volume, packed cell volume and viable cell count and prolonged the life span of EAC tumor bearing mice. Hematological profiles reverted to more or less normal levels in extract treated mice. The MECA also produced protective effect by decreasing the activity of serum enzymes, bilirubin and increase the protein and uric acid levels. MECA significantly (P < 0.05) decreased the levels of lipid peroxidation, while significantly (P < 0.05) increased the levels of glutathione content, vitamin C, vitamin E, superoxide dismutase and catalase CAT. The results indicate that MECA exhibited significant antitumor and antioxidant activity in EAC bearing mice.

Fabrication and electrical characterization of Au/p-Si/STO/Au contact

R.K. Gupta,K. Ghosh,P.K. Kahol 한국물리학회 2009 Current Applied Physics Vol.9 No.5

Au/STO/p-Si/Au structure is fabricated using pulsed laser deposition technique at room temperature. The current–voltage (I–V) characteristics of the device show rectification behavior. Various junction parameters such as ideality factor, barrier height and series resistance is determined using conventional forward bias I–V characteristics, Cheung method and Norde’s function. Au/STO/p-Si/Au structure shows non-ideal diode characteristics with the value of ideality factor of ~ 5.1 and barrier height of ~ 0.40 eV.

Biological and Impact Assessment Studies on Campoletis chlorideae Uchida: A Promising SolitaryLarval Endoparasitiod of Helicoverpa armigera (H bner)

R. K. Gupta,Desh Raj,Nirmala Devi 한국응용곤충학회 2004 Journal of Asia-Pacific Entomology Vol.7 No.2

We conducted laboratory and field studies to gain new understanding of biology and biocontrol potential of Campoletis chlorideae Uchida on Helicoverpa armigera (Hubner). Development time, adult longevity and fecundity of parasitoid were studied at 28±2℃ and 70±10% RH. It was revealed that the parasitoid laid on an average 13.40± 3.02 and 42.00±2.21 eggs after single mating and throughout its life span, respectively. The egg-larval and pupal period was 13.5±0.45 and 7.0±0.44 days, respectively. The emergence rate varied from 78.3 to 85.2%. The sex ratio of male: female in mated progeny was 1: 3.15±0.62. Adult longevity increased when provided with food source. Field release of 1-2 day old parasitoid with 15000 adults/ ha (sex ratio 1:3) in chickpea showed encouraging results, wherein significant reduction in pest population and pod damage and increase in yield was obtained. The significant increase in parasitism after 7 and 14 days of parasitoid release was also recorded. However, the level of parasitism obtained in field was lower and therefore certain habitat manipulation like crop diversification and kairomonal interventions could be possibly explored. Furthermore, sustained efforts for evolving superior strains that can perform well in given set of environmental conditions are also required.