Gram pod borer, Helicoverpa armigera (Hub.) is the major insect pest of pigeonpea and prediction of number of generations (no. of gen.) and generation time (gen. time) using growing degree days (GDD) ...approach during three future climate change periods viz., Near (NP), Distant (DP) and Far Distant (FDP) periods at eleven major pigeonpea growing locations of India was attempted. Multi-model ensemble of Maximum (Tmax) and Minimum (Tmin) temperature data of four Representative Concentration Pathways viz., RCP 2.6, 4.5, 6.0 and 8.5 of Coupled Model Inter comparison Project 5 (CMIP5) models was adopted here. The increase in projected Tmax and Tmin are significant during 3 climate change periods (CCPs) viz., the NP, DP and FDP over base line (BL) period under four RCP scenarios at all locations and would be higher (4.7-5.1 °C) in RCP 8.5 and in FDP. More number of annual (10-17) and seasonal (5-8) gens. are expected to occur with greater percent increase in FDP (8 to 38%) over base line followed by DP (7 to 22%) and NP (5to 10%) periods with shortened annual gen. time (4 to 27%) across 4 RCPs. The reduction of crop duration was substantial in short, medium and long duration pigeonpeas at all locations across 4 RCPs and 3 CCPs. The seasonal no.of gen. is expected to increase (5 to 35%) with shortened gen. time (4 to 26%) even with reduced crop duration across DP and FDP climate periods of 6.0 and 8.5 RCPs in LD pigeonpea. More no. of gen. of H. armigera with reduced gen. time are expected to occur at Ludhiana, Coimbatore, Mohanpur, Warangal and Akola locations over BL period in 4 RCPs when normal duration of pigeonpeas is considered. Geographical location (66 to 72%), climate period (11 to 19%), RCPs (5-7%) and their interaction (0.04-1%) is vital and together explained more than 90% of the total variation in future pest scenario. The findings indicate that the incidence of H. armigera would be higher on pigeonpea during ensuing CCPs in India under global warming context.
Graphene: The New Two-Dimensional Nanomaterial Rao, C.N.R; Sood, A.K; Subrahmanyam, K.S ...
Angewandte Chemie (International ed.),
October 5, 2009, Letnik:
48, Številka:
42
Journal Article
Recenzirano
Every few years, a new material with unique properties emerges and fascinates the scientific community, typical recent examples being high-temperature superconductors and carbon nanotubes. Graphene ...is the latest sensation with unusual properties, such as half-integer quantum Hall effect and ballistic electron transport. This two-dimensional material which is the parent of all graphitic carbon forms is strictly expected to comprise a single layer, but there is considerable interest in investigating two-layer and few-layer graphenes as well. Synthesis and characterization of graphenes pose challenges, but there has been considerable progress in the last year or so. Herein, we present the status of graphene research which includes aspects related to synthesis, characterization, structure, and properties.
Boron‐ and nitrogen‐doped graphenes are are prepared by the arc discharge between carbon electrodes or by the transformation of nanodiamond under appropriate atmospheres. Using a combination of ...experiment and theories based on first principles, systematic changes in the carrier‐concentration and electronic structure of the doped graphenes are demonstrated. Stiffening of the G‐band mode and intensification of the defect‐related D‐band in the Raman spectra are also observed.
Semiconductor metal oxides: Modifications, charge carrier dynamics and photocatalysis.
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•TiO2, WO3 and ZnO based photocatalysis is reviewed.•Advances to improve the efficiency are ...emphasized.•Differences and similarities in the modifications are highlighted.•Charge carrier dynamics for each strategy are discussed.
Metal oxide semiconductors (TiO2, WO3 and ZnO) finds unparalleled opportunity in wastewater purification under UV/visible light, largely encouraged by their divergent admirable features like stability, non-toxicity, ease of preparation, suitable band edge positions and facile generation of active oxygen species in the aqueous medium. However, the perennial failings of these photocatalysts emanates from the stumbling blocks like rapid charge carrier recombination and meager visible light response. In this review, tailoring the surface-bulk electronic structure through the calibrated and veritable approaches such as impurity doping, deposition with noble metals, sensitizing with other compounds (dyes, polymers, inorganic complexes and simple chelating ligands), hydrogenation process (annealing under hydrogen atmosphere), electronic integration with other semiconductors, modifying with carbon nanostructures, designing with exposed facets and tailoring with hierarchical morphologies to overcome their critical drawbacks are summarized. Taking into account the materials intrinsic properties, the pros and cons together with similarities and striking differences for each strategy in specific to TiO2, WO3 & ZnO are highlighted. These subtlety enunciates the primacy for improving the structure-electronic properties of metal oxides and credence to its fore in the practical applications. Future research must focus on comparing the performances of ZnO, TiO2 and WO3 in parallel to get insight into their photocatalytic behaviors. Such comparisons not only reveal the changed surface-electronic structure upon various modifications, but also shed light on charge carrier dynamics, free radical generation, structural stability and compatibility for photocatalytic reactions. It is envisioned that these cardinal tactics have profound implications and can be replicated to other semiconductor photocatalysts like CeO2, In2O3, Bi2O3, Fe2O3, BiVO4, AgX, BiOX (X=Cl, Br & I), Bi2WO6, Bi2MoO6, etc., to improve their competence for various environmental applications.
The characteristics of brick masonry are influenced by the properties of bricks and mortar. This paper attempts at studying the properties of brick masonry using table moulded bricks and wire-cut ...bricks of India with various types of mortars. The strength and elastic modulus of brick masonry under compression have been evaluated for strong-brick soft-mortar and soft-brick strong-mortar combinations. Various sizes of prisms and wallettes have been tested during these experiments to study the size effect and different bonding arrangements. The failure mechanisms of such specimens have been studied. Attempts are also made to derive empirical relationships for masonry strength as a function of brick and mortar strength in the Indian context.PUBLICATION ABSTRACT
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Interpenetrating polymeric network nanogels (IPN-NGs) composed of natural gelatin biological protein macromolecules and poly(acrylamidoglycolic acid) were produced by simple free ...radical emulsion polymerization. The developed IPN-NGs were characterized by Fourier-transform infra-red spectroscopy to confirm the formation of NGs. The hydrophobic curcumin drug was loaded successfully into these NGs using an in-situ method. The curcumin-encapsulated NGs were well dispersed in aqueous solutions and showed good bioavailability. Curcumin was dispersed molecularly in the IPN-NGs, which was confirmed by differential scanning calorimetry and X-ray diffraction. The NGs exhibited pH sensitive properties according to dynamic light scattering and the zeta size potentials. Transmission electron microscopy revealed the NGs to be spherical, approximately 100nm in size. The encapsulation efficiency of these IPN-NGs drug formulations ranged from 42 to 48%. In addition, the release of curcumin from the NGs was examined in phosphate buffer medium. The cytotoxicity of the IPN-NGs was studied using in vitro cultures of fibroblasts and a colorectal cancer cell line. The results suggest that the newly developed pH sensitive gelatin-poly(acrylamidoglycolic acid)-curcumin NGs can be applied for colorectal cancer drug delivery applications.
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► GWP were highest in rice straw+green manure treatment. ► The labile carbon pools were highest in rice straw+green manure treatment. ► Combined application of rice straw+urea was the ...most adoptable. ► Urea as single application had low capacity of carbon storage.
Effects of four years of inorganic and organic nitrogen (N) management on the emission of three major greenhouse gases (GHGs): methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O), and on soil labile carbon fractions such as water-soluble carbon (C, WSC), microbial biomass carbon (MBC), KMnO4 oxidizable organic carbon (KMnO4-C), carbon management index (CMI) and soil carbon storage were investigated in a flooded rice (Oryza sativa L.) field in India. The treatments included an unfertilized control, inorganic nitrogen fertilizer, rice straw+inorganic nitrogen fertilizer and rice straw+green manure. Maximum global warming potential (GWP) (10,188kgCO2equivalent ha−1) was determined for the combined application of rice straw and green manure. Total carbon content and carbon storage in the topsoil were significantly increased for the rice straw+inorganic nitrogen fertilizer treatment. The combined application of rice straw and green manure was more effective in increasing WSC, MBC, KMnO4-C concentrations and CMI than the inorganic fertilizer treatments, although it increased gaseous carbon emission. The combined application of rice straw and an inorganic fertilizer was most effective in sequestrating soil organic carbon (1.39Mgha−1), resulting in a higher grain yield. Therefore, it could be the best option for improving productivity and carbon storage in the rice–rice cropping system.
Salinity tolerance in rice is highly desirable to sustain production in areas rendered saline due to various reasons. It is a complex quantitative trait having different components, which can be ...dissected effectively by genome-wide association study (GWAS). Here, we implemented GWAS to identify loci controlling salinity tolerance in rice. A custom-designed array based on 6,000 single nucleotide polymorphisms (SNPs) in as many stress-responsive genes, distributed at an average physical interval of <100 kb on 12 rice chromosomes, was used to genotype 220 rice accessions using Infinium high-throughput assay. Genetic association was analysed with 12 different traits recorded on these accessions under field conditions at reproductive stage. We identified 20 SNPs (loci) significantly associated with Na(+)/K(+) ratio, and 44 SNPs with other traits observed under stress condition. The loci identified for various salinity indices through GWAS explained 5-18% of the phenotypic variance. The region harbouring Saltol, a major quantitative trait loci (QTLs) on chromosome 1 in rice, which is known to control salinity tolerance at seedling stage, was detected as a major association with Na(+)/K(+) ratio measured at reproductive stage in our study. In addition to Saltol, we also found GWAS peaks representing new QTLs on chromosomes 4, 6 and 7. The current association mapping panel contained mostly indica accessions that can serve as source of novel salt tolerance genes and alleles. The gene-based SNP array used in this study was found cost-effective and efficient in unveiling genomic regions/candidate genes regulating salinity stress tolerance in rice.
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► We have developed poly(N-vinyl caprolactam-co-acrylamidoglycolic acid) based nanogels for controlled release of an anticancer drugs. ► This system exhibited dual responsive nature, ...and accelerated drug release profile. ► The cumulative release data were analysed using an emperical equation to compute the diffusion coefficient; it suggest Fickian diffusion.
A series of novel nanogels (NGs) with both pH and thermoresponsive properties were synthesised by free radical emulsion polymerisation of N-vinyl caprolactam (VCL) and acrylamidoglycolic acid (AGA). 5-Flurouracil, an anti cancer drug, was successfully loaded into these nanogels via equilibrium swelling method. The encapsulation efficiency of 5-FU was found up to 61%. Here we present the novel potential drug delivery system showing both pH and temperature release of 5-FU. Fourier transforms infrared spectroscopy (FTIR), and differential scanning calorimetric (DSC) examined the structure and morphology of the NGs. Transmission electron microscopy (TEM) indicates the diameter of the NGs to be about 50nm. The size distribution of NGs was investigated using dynamic light scattering (DLS), the average diameter and polydispersity is 57nm and 0.194. Interestingly, the in vitro release studies of 5-FU demonstrated the dual nature (pH and temperature) of NGs. The cumulative release data were analysed using an emperical equation to compute the diffusion exponent (n); whose values suggest Fickian diffusion.
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