Showing papers by "Bharathiar University published in 2004"
TL;DR: P pH effect and desorption studies showed that adsorption occurred by both ion exchange and chemisorption mechanisms, and was found to be spontaneous and endothermic.
251 citations
TL;DR: The current information available on the incidence of mycorrhiza in sedges and the possible reasons for low mycotrophy observed in the family Cyperaceae is reviewed.
Abstract: Most terrestrial plants associate with root-colonising mycorrhizal fungi, which improve the fitness of both the fungal and plant associates. However, exceptions exist both between and within plant families failing to associate with mycorrhizal fungi or in the incidence and the extent of mycotrophy, which may vary greatly. Sedges are important pioneers of disturbed habitats and often dominate vegetations like wetlands, and arctic and alpine vegetations, in which the mycorrhizal inoculum in the soil is often low or absent. In the past, sedges were often designated as non-mycorrhizal, though limited reports indicated the presence of mycorrhiza in certain species. However, studies since 1987 indicate widespread occurrence of mycorrhiza in sedges. Based on these studies, the family Cyperaceae is no longer a non-mycorrhizal family, but the mycorrhizal status of its members is greatly influenced by environmental conditions. Further, sedges appear to have several morphological adaptations to thrive in the absence of mycorrhizal association. Though mycorrhizal associations have been noted in many sedge species, the ecological role of this association is not well documented and no clear generalisation can be drawn. Similarly, the role of mycorrhizal fungi on sedge growth and nutrient uptake or non-nutritional benefits has yet to be fully ascertained. This paper reviews the current information available on the incidence of mycorrhiza in sedges and the possible reasons for low mycotrophy observed in this family.
144 citations
TL;DR: The analysis on 3D structures of protein kinases that revealed features distinct to active states of Ser/Thr and Tyr kinases are described to aid in the understanding of mechanisms underlying the control of the catalytic activity of distinct subgroups ofprotein kinases.
138 citations
TL;DR: An octahedral structure has been confirmed for the complexes that were characterized by elemental analyses, Infra red, electronic, electron paramagnetic resonance spectroscopy and cyclic voltammetry and screened for their antibacterial properties.
126 citations
TL;DR: Theoretical methods have been used to study the proper and improper hydrogen bonds, considering the hydrogen bond length, interaction energy, and charge transfer, for some hydrogen-bonded complexes as discussed by the authors.
109 citations
TL;DR: Biopesticides are relatively safe and biodegradable; a synergistic effect of botanical insecticides and bacterial toxins was found; less expensive, readily available and naturally occurring biopesticide could be an alternative for organic and inorganic pesticides in controlling RLF.
Abstract: The effect of botanical insecticides and bacterial toxins on gut enzyme activity of larvae of the rice leaffolderCnaphalocrocis medinalis (Guenee) (Insecta: Lepidoptera: Pyralidae) was investigated. Gut enzyme activities were affected by botanical insecticides and bacterial toxin individually and in combination. When fed a diet of rice leaves treated with botanical insecticides and bacterial toxins, in bioassays the activities of gut tissue enzymes — acid phosphatases (ACP), alkaline phosphatases (ALP) and adenosine triphosphatases (ATPase) — of rice leaffolder larvae were affected. When combined, the effect was more severe at a low concentration. Larvae that were chronically exposed to botanical insecticides and bacterial toxins showed a reduction in weight (59–89%) and exhibited a significant reduction in ACP, ALP and ATPase activities. The combination ofBacillus thuringiensis kurstaki and botanical insecticides caused a decrease of twofold in enzyme activity even at reduced concentration. A synergistic effect was found when botanical insecticides and bacterial toxins were combined at low doses. These effects were most pronounced in early instars. Clear dose-response relationships were established with respect to enzyme activity. In conclusion: (i) biopesticides are relatively safe and biodegradable; (ii) a synergistic effect of botanical insecticides and bacterial toxins was found; (iii) less expensive, readily available and naturally occurring biopesticides could be an alternative for organic and inorganic pesticides in controlling RLF.
103 citations
TL;DR: In diabetes, liver and kidney tissues are more vulnerable to oxidative stress and show increased lipid peroxidation, so Gymnema montanum leaf extract may be anticipated to have biological significance in eliminating reactive free radicals that may otherwise affect normal cell functioning.
98 citations
TL;DR: In this paper, the influence of the addition of plasticizer (DMF) on the ionic conductivity of the PVAc-LiClO 4 polymer electrolyte complex has been discussed.
93 citations
TL;DR: In this paper, the formation of a polymer- salt complex has been confirmed by FT-IR spectral studies, where the polymer electrolytes composed of a blend of poly (vinyl acetate) (PVAc) and poly (methylmethacrylate) (PMMA) as a host polymer and LiClO4 as a salt are prepared by a solution casting technique.
Abstract: The polymer electrolytes composed of a blend of poly (vinyl acetate) (PVAc) and poly (methylmethacrylate) (PMMA) as a host polymer and LiClO4 as a salt are prepared by a solution casting technique. The formation of blend polymer- salt complex has been confirmed by FT-IR spectral studies. The conductivity- temperature plots are found to follow an Arrhenius nature. Arrhenius plot shows the decrease in activation energy with the increase in salt concentration. The dielectric behaviour of the sample is analysed using dielectric permittivity (e′), dielectric loss (e″) and electric modulus (M″) of the samples. The impedance cole- cole plot shows the high frequency semi- circle is due to the bulk effect of the material and the depression in the semicircle shows the non-Debye nature of the material. The bulk conductivity is found to vary between 2.5×10−5 Scm−1 to 1.7×10−3 Scm−1 with the increase of salt concentration of blend polymer samples. The migration energy derived from the dissipation factor is almost equal to the activation energy calculated from conductivity. The modulus spectrum of the samples shows the non-Debye behaviour of the polymer electrolyte films. The low frequency dispersion of the dielectric constant implies the space charge effects arising from the electrodes.
83 citations
TL;DR: The K(c) values for the binuclear complexes have been found to be low because of the fact that two acetylacetone units of the bridging tae ligand are not in the same plane, as revealed by the crystal structure of [[Ru(acac)(2)](2)(tae)].
Abstract: Binuclear β-diketonatoruthenium(III) complexes [{Ru(acac)2}2(tae)], [{Ru(phpa)2}2(tae)], and [(acac)2Ru(tae)Ru(phpa)2] and binuclear and mononuclear bipyridine complexes [{Ru(bpy)2}2(tae)](PF6)2 an...
66 citations
TL;DR: In this paper, the ability of Pleurotus spp., P. sajor-caju; P. platypus and P. citrinopileatus to treat pulp and paper mill effluent on a laboratory and pilot scale were studied.
Abstract: In this work, the ability of Pleurotus spp.:P. sajor-caju; P. platypus and P. citrinopileatus to treat pulp and paper mill effluent on a laboratory and pilot scale were studied. On the laboratory scale treatment, P. sajor-caju decolorized the effluent by 66.7% on day 6 of incubation. Inorganic chloride liberated by P. sajor-caju was 230.9% (814.0 mg/dl) and the COD was reduced by 61.3% (1302.0 mg/dl) on day 10 of treatment. In the pilot scale treatment maximum decolorization was obtained by P. sajor-caju (60.1%) on day 6 of the incubation. Inorganic chloride content was increased by 524.0 mg/dl (113.0%) and the COD was reduced by 1442.0 mg/dl (57.2%) by P. sajor-caju on day 7 of incubation. These results revealed that the treatment of pulp and paper mill effluent by P. sajor-caju proved as better candidate for the purpose than P. platypus and P. citrinopileatus.
TL;DR: In this article, a proton conducting polymer electrolyte of pure polyvinyl alcohol and polyvinel alcohol complexed with ammonium acetate having different compositions have been prepared by solution cast technique.
Abstract: A proton conducting polymer electrolytes of pure polyvinyl alcohol and polyvinyl alcohol complexed with ammonium acetate having different compositions have been prepared by solution cast technique. FTIR spectrum confirms the complexation process. The conductivity of the pure polyvinyl alcohol is in the order 10−10 S/cm at ambient temperature and its value increases 104 times when complexed with 20% ammonium acetate. The Arrhenius plot for all electrolyte shows two different regions above and below the glass transition temperature. A high dielectric loss value is observed for the case of complexed PVA in comparison to pure PVA. Based on the study of relaxation spectra, it is found that the relaxation time decreases with increase in temperature and dopant concentration.
TL;DR: It is concluded that the phenotypic similarities of some Indian groups to Africans do not reflect a close relationship between these groups, but are better explained by convergence.
Abstract: Summary We describe the genetic structure and affinities of five Dravidian-speaking tribal populations inhabiting the Nilgiri hills of Tamil Nadu, in south India, using 24 autosomal DNA markers. Our goals were: (i) to examine what evolutionary forces have most significantly impacted south Indian tribal genetic variation, and (ii) to test whether the phenotypic similarities of some south Indian tribal groups to Africans represent a signature of close relationship to Africans or are due to convergence. All loci were polymorphic and average heterozygosities were substantial (range: 0.347‐0.423). Genetic differentiation was high (Gst = 6.7%) and genetic distances were not significantly correlated with geographic distances. Genetic drift therefore probably played a significant role in shaping the patterns of genetic variation observed in southern Indian tribal populations. Otherwise, analyses of population relationships showed that Indian populations are closely related to one another, regardless of phenotypic characteristics, and do not show particular affinities to Africans. We conclude that the phenotypic similarities of some Indian groups to Africans do not reflect a close relationship between these groups, but are better explained by convergence.
TL;DR: In this paper, the adsorption of catechol onto Fe(III)/Cr(III) hydroxide was investigated to assess the possible use of this adsorbent.
Abstract: The adsorption of catechol onto “waste” Fe(III)/Cr(III) hydroxide was investigated to assess the possible use of this adsorbent. The influence of various parameters such as agitation time, catechol concentration, adsorbent dose, pH, and temperature has been studied. Equilibrium adsorption data followed both Langmuir and Freundlich isotherms. Adsorption followed second-order rate kinetics. The Langmuir adsorption capacity (Qo) was found to be 4.0 mg/g of the adsorbent. Acidic pH was favorable for the adsorption of catechol. Desorption studies showed that chemisorption seems to be the major mode of the adsorption process. Thermodynamic parameters such as ΔG°, ΔH°, and ΔS° for the adsorption were evaluated.
TL;DR: In this paper, structural, Raman and optical properties of Cd0.6Zn0.4Te polycrystalline thin films deposited onto well cleaned corning glass substrates by vacuum evaporation were investigated.
Abstract: We report the structural, Raman and optical properties of Cd0.6Zn0.4Te polycrystalline thin films deposited onto well cleaned corning glass substrates by vacuum evaporation. X-ray diffraction pattern showed that the incorporation of zinc favours the growth of films preferentially oriented parallel to the (1 1 1) planes of cubic CdTe. The optical response of vacuum evaporated Cd0.6Zn0.4Te films in the 1.5–5.5 eV photon energy range at room temperature has been studied by spectroscopic ellipsometry. The measured dielectric-function spectra reveal distinct structures at energies of the E1 (3.53 eV), E1+Δ1 (3.9 eV) and E2 (5 eV) critical points corresponding to the interband transitions. In order to check the film local atomic order, the samples were studied by Raman spectroscopy. The transverse and longitudinal optic modes regularly found in CdTe and ZnTe were also observed in Cd0.6Zn0.4Te thin films. From the optical transmittance and absorption coefficient, the band gaps of the films are found to be direct allowed.
TL;DR: In this article, the conformational stability of neutral molecules and their zwitterionic forms using density functional theory (DFT) methods was studied using the potential energy surface scan employing the DFT methods.
Abstract: The conformational stability of Glycine, Alanine and their zwitterionic forms have been studied using density functional theory (DFT) methods. The conformers have been predicted by the Potential energy surface scan employing the DFT methods, B3LYP, B3PW91 and B3P86 implementing 6-311++G** basis set. The rotational potential energy curves for neutral molecules and zwitterionic form have been determined at the above levels of theory. The Fourier decomposition potentials were analysed for the above molecules. The B3LYP level of theory predicts conformer 1 as the most stable one, but B3PW91 and B3P86 levels of theory have predicted conformers 2n, 2b for glycine and alanine respectively. The chemical hardness calculated at the HF/6-311++G** level of theory shows that the Maximum hardness principle fails to predict the conformational stability for hydrogen bonded systems.
TL;DR: In this paper, conductance measurement, IR spectral and thermal analyses have been carried out on hydrazinium salts of benzene tricarboxylic and tetracarboxyl acids.
TL;DR: In this paper, the optical constants of Cd 0.2 Zn 0.8 Te thin films deposited at different substrate temperatures are calculated in the wavelength range 400-2500nm. And effective crystallite size and strain are determined by the method of variance analysis of the X-ray diffraction line profiles for the films.
TL;DR: A formal test of the demic versus cultural diffusion models of the spread of agriculture in India reveals that recent south Indian agriculturalists are overall genetically more similar to traditional agriculturalists than to traditional hunter-gatherers.
Abstract: The process by which agriculture diffused from the Fertile Crescent within the past 10,000 years has been widely discussed, but as yet there is no consensus: Was it mostly a demic diffusion (with massive spread of people) or rather a cultural diffusion (without substantial migration of people)? The demic diffusion model ([ 1 ][1]) predicts a substantial genetic input from migrating agriculturalists, whereas the cultural diffusion model ([ 2 ][2]) predicts no major changes at the genetic level. Hence, a way to test these competing hypotheses would be to compare genetic variation in traditional agriculturalists, traditional hunter-gatherers, and recent agriculturalists (i.e., former hunter-gatherers who recently shifted to agriculture). Under the demic diffusion model, recent agriculturalists are expected to show closer genetic affinities to traditional agriculturalists than do hunter-gatherers; whereas under the cultural diffusion model, recent agriculturalists should resemble hunter-gatherers genetically.
Genetic studies of Europeans have led to conflicting conclusions, partly because the genetic composition of pre-agricultural European populations is unknown. However, there still exist in India both nonagricultural groups and groups that recently adopted agriculture ([ 3 ][3], [ 4 ][4]), allowing a formal test of the demic versus cultural diffusion models of the spread of agriculture. Caste groups can be considered as traditional agriculturalists in this context, because they introduced key innovations (such as iron technology) that facilitated the expansion of agriculture toward south India ([ 4 ][4]). There are also tribal groups in south India who are generally considered to be the aboriginal inhabitants of the region and who have traditionally been hunter-gatherers ([ 3 ][3], [ 4 ][4]). Some of them still survive through hunting and gathering or unskilled labor, whereas others have shifted to an agriculturalist subsistence strategy within the past 3000 years ([ 4 ][4]).
Genetic affinities were deduced from the frequencies of 14 Y-chromosome haplogroups analyzed in 583 males, including 71 tribal south Indian hunter-gatherers, 60 tribal south Indian recent agriculturalists, and 283 south Indian and 169 north Indian traditional agriculturalists ([ 5 ][5]). Pairwise genetic (Fst) distances separating the different categories of individuals indicate that south Indian recent agriculturalists are significantly more closely related to traditional agriculturalists than are traditional hunter-gatherers ([Fig. 1A][6]) ( t test on jackknifed Fst values, P < 0.01). This conclusion is supported by a multidimensional scaling analysis that simultaneously compared all four categories; it also reveals that recent south Indian agriculturalists are overall genetically more similar to traditional agriculturalists than to traditional hunter-gatherers ([Fig. 1B][6]).
![ Fig. 1. ][7] Fig. 1.
Genetic affinities between southern traditional hunter-gatherers (Trad. HG south), southern recent agriculturalists (Recent AG south), southern traditional agriculturalists (Trad. AG south), and northern traditional agriculturalists (Trad. AG north). ( A ) Fst distances were deduced from Y chromosome (below diagonal) and mtDNA (above diagonal) data. ( B and C ) Multidimensional scaling plots were based on (B) Y chromosome and (C) mtDNA Fst distances. SV, stress value.
Genetic affinities were also deduced from sequences of the mitochondrial DNA (mtDNA) control region analyzed in 632 individuals, including 229 tribal south Indian hunter-gatherers, 201 tribal south Indian recent agriculturalists, and 140 south Indian and 62 north Indian traditional agriculturalists ([ 5 ][5]). Pairwise Fst distances separating the different categories of individuals indicate that south Indian recent agriculturalists are significantly more closely related to traditional agriculturalists than are traditional hunter-gatherers ([Fig. 1A][6]) ( t test on jackknifed Fst values, P < 0.001). This conclusion is also supported by a multidimensional scaling analysis ([Fig. 1C][6]); the latter also shows that recent south Indian agriculturalists are overall genetically more similar to traditional agriculturalists than to traditional hunter-gatherers. Thus, mtDNA variation shows trends that markedly parallel those deduced from Y-chromosome variation. This is also reflected in the fact that mtDNA and Y-chromosome genetic distances among traditional and recent agriculturalists and traditional hunter-gatherers are highly and significantly correlated (Mantel test, r2 = 0.805, P < 0.05).
The patterns of Y-chromosome and mtDNA variation in south India indicate that groups that have changed recently from a hunting-gathering subsistence strategy to agriculture have concomitantly received genes from traditional agriculturalists. This demonstrates the validity of the demic diffusion model for the spread of agriculture to India. It also underscores the importance of cultural processes such as the diffusion of agriculture in shaping human genetic variation.
Supporting Online Material
[www.sciencemag.org/cgi/content/full/304/5674/1125/DC1][8]
Materials and Methods
References and Notes
1. [↵][9] A. J. Ammerman, L. L. Cavalli-Sforza, Neolithic Transition and the Genetics of Populations in Europe (Princeton Univ. Press, Princeton, NJ, 1984).
2. [↵][10] A. Whittle, Europe in the Neolithic (Cambridge Univ. Press, Cambridge, 1996).
3. [↵][11] K. S. Singh, People of India: India's Communities (Oxford Univ. Press, Delhi, 1998).
4. [↵][12] V. N. Misra, J. Biosci. 26, 491 (2001).
[OpenUrl][13][PubMed][14][Web of Science][15]
5. [↵][16] Materials and methods are available as supporting material on Science Online.
6. We thank P. P. Majumder and M. V. Usha Rani for assistance. Supported by the Max Planck Society (Germany) and the Indian Department of Biotechnology.
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[7]: pending:yes
[8]: http://www.sciencemag.org/cgi/content/full/304/5674/1125/DC1
[9]: #xref-ref-1-1 "View reference 1 in text"
[10]: #xref-ref-2-1 "View reference 2 in text"
[11]: #xref-ref-3-1 "View reference 3 in text"
[12]: #xref-ref-4-1 "View reference 4 in text"
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[16]: #xref-ref-5-1 "View reference 5 in text"
TL;DR: Data of high ratios of AAA associated at young stages with cholinesterases strongly indicate a role of AAA in early brain development.
Abstract: Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are known to exhibit aryl acylamidase activities (here called AAAAChE and AAABChE, respectively), which have been suggested to be involved in developmental and pathological processes. We here have investigated the developmental profiles of both AAAAChE and AAABChE activities along with their AChE and BChE activities from embryonic days E3 to hatching (E21) in Triton-extracted homogenates from chicken embryonic brains. AAAAChE follows continuously an increase that is typical for AChE expression itself, whereas AAABChE was relatively high before E10 to then become negligible toward hatching. Sucrose gradient centrifugation of both homogenized and immunopurified samples from E6–E18 brains showed that all globular forms (G1, G2, G4) of AChE present AAAAChE activity. Interestingly, the ratio of AAAAChE to AChE is highest at E6, and here again higher on G1/G2- over the G4-form. Noticeably, the sensitivity of AAAAChE toward the specific AChE inhibitor BW284c51 at all stages is higher than that of AChE itself. These data of high ratios of AAA associated at young stages with cholinesterases strongly indicate a role of AAA in early brain development.
TL;DR: Zn 0.52 Se 0.48 /Si Schottky diodes are fabricated by depositing zinc selenide thin films onto Si(1/0/0) substrates by vacuum evaporation technique as mentioned in this paper.
Abstract: Zn 0.52 Se 0.48 /Si Schottky diodes are fabricated by depositing zinc selenide (Zn 0.52 Se 0.48 ) thin films onto Si(1 0 0) substrates by vacuum evaporation technique. Rutherford backscattering spectrometry (RBS) analysis shows that the deposited films are nearly stoichiometric in nature. X-ray diffractogram of the films reveals the preferential orientation of the films along (1 1 1) direction. Structural parameters such as crystallite size ( D ), dislocation density ( δ ), strain ( e ), and the lattice parameter are calculated as 29.13 nm, 1.187 × 10 −15 lin/m 2 , 1.354 × 10 −3 lin −2 m −4 and 5.676 × 10 −10 m respectively. From the I – V measurements on the Zn 0.52 Se 0.48 /p-Si Schottky diodes, ideality and diode rectification factors are evaluated, as 1.749 (305 K) and 1.04 × 10 4 (305 K) respectively. The built-in potential, effective carrier concentration ( N A ) and barrier height were also evaluated from C – V measurement, which are found to be 1.02 V, 5.907 × 10 15 cm −3 and 1.359 eV respectively.
TL;DR: In this paper, the adsorption of mercury(II) from aqueous solutions onto an activated carbon derived from Eichhornia crassipes (AEC) was investigated under varying conditions of agitation time, metal ion concentration, adsorbent dose and pH to assess the kinetic and equilibrium parameters.
Abstract: The adsorption of mercury(II) from aqueous solutions onto an activated carbon derived from Eichhornia crassipes (AEC) was investigated under varying conditions of agitation time, metal ion concentration, adsorbent dose and pH to assess the kinetic and equilibrium parameters. Adsorption equilibrium was attained in 200, 310, 360 and 360 min for 10, 20, 30 and 40 mg/l Hg(II) concentrations. The first- and second-order adsorption rate constants were calculated and the experimental equilibrium adsorption capacities (qe ) for different initial Hg(II) concentrations were reported. Adsorption was dependent on the solution pH, the Hg(II) concentration, the carbon concentration and the contact time. Both the Freundlich and Langmuir adsorption isotherm models fitted the experimental data well. The adsorption capacity was found to be 28.4 mg/g at pH 5 for a particle size of 125–180 μm. The adsorption capacity of the carbon produced met commercial conditions and was found to be superior to that of many other adsorbent...
TL;DR: In this paper, dry Chinese Reed (Miscanthus sinensis) was used as an adsorbent for the removal of Cr(III) from tannery wastewater, and the results showed that both ion exchange and chemisorption are involved in the adsorption process.
Abstract: Dried Chinese Reed (Miscanthus sinensis) was investigated as adsorbent for the removal of Cr(III) from tannery wastewater. Batch mode adsorption studies were conducted using aqueous solutions of Cr(III). Parameters studied include Cr(III) concentration, agitation time, adsorbent dose and pH. Adsorption followed pseudo-second order kinetic model. Equilibrium adsorption data obeyed both Langmuir and Freundlich isotherms. Langmuir adsorption capacity was found to be 1.85 mg/g. Effects of pH on adsorption and desorption show that both ion exchange and chemisorption are involved in the adsorption process.
TL;DR: In this article, Ab initio and DFT methods have been used to study the five tautomeric forms of indazole (IZT1, IZT2, IzT3, IizT4, IIZT5) in gaseous and aqueous phases.
Abstract: Ab initio and DFT methods have been used to study the five tautomeric forms of indazole (IZT1, IZT2, IZT3, IZT4, IZT5) in gaseous and aqueous phases. The tautomers in gas phase have been optimized at MP2/6-311G(2d,2p), B3LYP/6-311G(2d,2p) and B3PW91/6-311G(2d,2p) levels of theory. The self-consistent reaction field theory (SCRF) has been used to optimize the tautomers in aqueous phase (e=78.5) at B3LYP/6-311G(2d, 2p) level of theory and the solvent effect has been studied. The structure, energetics and relative stabilities of the tautomers were compared and analyzed both in gaseous and aqueous phases. The principle of maximum hardness has been tested by calculating chemical hardness and chemical potential at HF/6-311G(2d,2p) level of theory to predict the order of stability of the tautomers. The condensed Fukui functions have been calculated to identify the relative change in most reactive site of the optimized tautomers in gas phase using atomic charges obtained through Mulliken population analysis scheme. 13C-NMR studies have been carried out for these tautomers in the gas phase at B3LYP/6-311G(2d,2p) level of theory on the basis of Cheeseman co-worker's method and the results were discussed.
TL;DR: In this paper, the SCLC parameters such as free carrier density (p 0), trap density (pt), the ratio between free carriers density to the total carrier density, mobility, and effective hole mobility were calculated.
Abstract: Polyaniline emeraldine base (PANI-EB) powder was synthesized by oxidative polymerization of aniline. The PANI-EB films were prepared by the solution-casting technique. The temperature-dependent dc conductivity measured in the range 173–303 K suggests that the PANI-EB is a quasi-one-dimensional disordered conductor. The current-voltage characteristics of the PANI-EB films measured in the range 333–383 K showed the SCLC mechanism. The SCLC parameters such as free carrier density (p0), trap density (pt), the ratio between free carrier density to the total carrier density (θ), mobility (µ) and the effective hole mobility (µeff) were calculated. The activation energy (Ea = 0.32 eV) and the Fermi level (EF = 0.42 eV) were estimated. As well as these, the trap parameters such as the trap filled limit voltage (VTFL), the shallow trap density (Nt), the depth of the dominant trap level (Et − Ev), the density of states within the hole mobility edge (Nv) and the characteristic energy (Ec) were also calculated and presented. The exponential type of traps distribution with large number of traps was found to be due to the disorder and moisture in the polymer films. Copyright © 2004 Society of Chemical Industry
TL;DR: Findings indicate that G. montanum leaf extract possesses antiperoxidative and antioxidant effects in addition to its antidiabetic activity, suggesting a role in protective action against lipid peroxidation-mediated membrane damage.
Abstract: The effects of leaf extract from Gymnema montanum, an endangered and endemic plant, were examined on brain lipid peroxidation in experimental diabetic rats. Ethanolic extract of G. montanum leaves was administered orally (50, 100, and 200 mg/kg of body weight) for 3 weeks, and changes in blood glucose, plasma insulin, and lipid peroxidation markers such as thiobarbituric acid-reactive substances (TBARS), hydroperoxides, and levels of antioxidants, namely, superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione, and glutathione-S-transferase, were examined in the brain of alloxan-induced diabetic rats. Glibenclamide was used as a standard reference drug. A significant increase in the activities of antioxidants was observed in brain on treatment with G. montanum leaf extract and glibenclamide for 3 weeks. Both the treated groups showed significant decreases in formation of TBARS and hydroperoxides in brain, suggesting a role in protective action against lipid peroxidation-mediated membrane damage. Our findings indicate that G. montanum leaf extract possesses antiperoxidative and antioxidant effects in addition to its antidiabetic activity. This report helps to create awareness on the need for conservation of medicinal plants, and G. montanum is one such plant that needs to be conserved through various propagation trials.
TL;DR: The extracts of leaf, root, stem, and the callus obtained from Pseudarthria viscida showed significant inhibitory activity against some fungal pathogens causing major diseases in crop plants and stored food grains.
TL;DR: In this article, the hexagonal phase LaF3 film has been detected by using glancing angle XRD analysis and structural parameters such as lattice constants, grain size and micro-strain has been calculated from the XRD data.
TL;DR: In this article, the authors used high temperatures and steep temperatures present in thermal plasma is exploited to spheroidize particles in the size range from 40-100 μm to achieve uniform feeding of powders into a plasma jet.
Abstract: Thermal spray coatings of surfaces with metal, alloy and ceramic materials for protection against corrosion, erosion and wear is an intense field of research. The technique involves injection of the powder into a plasma flame, melting, acceleration of the powder particles, impact and bonding with the substrate. Feedstock powders of metals, alloys and ceramics for thermal spray applications have to meet several requirements. Particle shape, size and its distribution, powder flow characteristics and density are the important factors to be considered in order to ensure high spray efficiency and better coating properties. For smooth and uniform feeding of powders into plasma jet, the powder particles have to be spherical in shape. High temperatures and steep temperatures present in thermal plasma is exploited to spheroidize particles in the present investigation. Nickel powder particles in the size range from 40–100 μm were spheroidized using plasma processing. SEM and optical micrographs showed spherical shape of processed particles.