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Rhizoctonia solani AG1-IA is a polyphagous basidiomycete fungal pathogen that causes sheath blight disease in rice. In a high-quality genome assembly-based analysis, we report a recent whole genome duplication in R. solani AG1-IA. Duplicated syntenic gene blocks showed presence of district clusters of transposable elements (TEs), which introduced disruption in the continuity of synteny and caused alterations in gene structures. Genome duplication followed by TE-mediated gene structure alterations caused neofunctionalization of genes associated with pathogenicity, as experimentally shown by variation in expression patterns and their involvement during plant colonization. High throughput genome sequencing of forty-two rice field isolates of R. solani AG1-IA from different agro-climatic zones of India profiled the population genetic structure of the Indian isolates and classified those into three distinct groups and a subgroup of admixture, emphasizing exchange of genetic material under field conditions. Genetic diversity analysis of this population predicted the regions that are that are targets for diversifying and purifying selections. Experimental evidence showed that the genes undergoing diversifying and purifying selections were essential for pathogenicity. Together, our data and the analysis revealed profound impact of genome duplication and the transposable elements on genomic diversity and evolution that shaped the pathogenicity of R. solani AG1- IA.

Defect engineering in thermoelectric (TE) materials enables the alteration of the crystal lattice by creating an atomic scale disorder, which can facilitate a synergistic modulation of the electric...

Phytopathogens have evolved mechanisms to utilize host genes (commonly known as susceptibility factors) to promote their pathogenesis. Rhizoctonia solani is a highly destructive fungal pathogen of various plants, including rice. We previously reported rice genes that were differentially regulated during R. solani pathogenesis. In this study, we analyzed the role of tomato homologs of two rice genes, isoflavone reductase (IFR) and alternative NADH:ubiquinone oxidoreductase (NUOR), as potential susceptibility factors for R. solani. Virus-induced gene silencing of NUOR in tomato resulted in compromised susceptibility against R. solani, whereas IFR-silenced plants demonstrated susceptibility similar to that of control plants. NUOR silencing in tomato led to homogenous accumulation of reactive oxygen species (optimum range) upon R. solani infection. In addition, the expression and enzyme activity of some host defense and antioxidant genes was enhanced, whereas H2O2 content, lipid peroxidation, and electrolyte leakage were reduced in NUOR-silenced plants. Similarly, transient silencing of OsNUOR provided tolerance against R. solani infection in rice. Overall, the data presented in this study suggest that NUOR serves as a host susceptibility factor to promote R. solani pathogenesis.

The Rhizoctonia solani species complex is comprised of strains belonging to different anastomosis groups and causes diseases in several economically important crops, including rice. However, individuals within same anastomosis group exhibit distinct morphological and pathological differences on the same host. In this study, we have sequenced the genome of two aggressive Indian strains (BRS11 and BRS13) belonging to AG1-IA anastomosis group and compared them with the available genome of R. solani AG1-IA. We identified several SNPs and Indels in both of these genomes, in comparison to the AG1-IA genome. Furthermore, we observed expansion and emergence of orthogroups in these Indian strains and identified those potentially associated with pathogenesis. Amongst them, transposable elements, cell wall degrading enzymes, transcription factors, and oxalate decarboxylase were noteworthy. The current study unravels genetic variations and identifies genes that might account for pathogenicity variations amongst R. solani strains.

Here, we report a thermoelectric material, Sn-doped Cu3SbSe4, with a figure-of-merit (ZT) of unity, which is stable up to 623 K. The Cu3SbSe4 samples, individually doped with Bi, Pb and Sn, were synthesized using conventional vacuum melting followed by the spark plasma sintering. The first-principle density functional theory (DFT) based calculations suggest that these doped Cu3SbSe4 compounds have negative formation energy throughout the temperature range, suggesting their chemical/thermal stability. The current study is to support the synchronization of theoretical and experimental study and pre-screening of the dopant which ensures stability and the TE performance. Among all the dopants studied, we realized a ZTmax ∼1 at 623 K with Sn doping for the optimized composition Cu3Sb0.985Sn0.015Se4 owing to the favourable optimization of the electrical and thermal transport properties. This is also supported by the DFT calculations, which suggests that Sn-doping leads to a decrease in lattice thermal conductivity.

Microbiome plays an important role in plant growth and adaptation to various environmental conditions. The cross-talk between host plant and microbes (including microbe-microbe interactions) plays a crucial role in shaping the microbiome. Recent studies have highlighted that plant microbiome is enriched in genes encoding enzymes and natural products. Several novel antimicrobial compounds, bioactive natural products and lytic/degrading enzymes with industrial implications are being identified from the microbiome. Moreover, advancements in metagenomics and culture techniques are facilitating the development of synthetic microbial communities to promote sustainable agriculture. We discuss the recent advancements, opportunities and challenges in harnessing the full potential of plant microbiome.

Recently, the demand of the material manipulation with specific design is highly required for several strategic and societal applications such as in defence, nuclear, security, space, waste management, renewable energy generation and storage. To address these challenges, it is important to design the materials synergetically fit according to their demand in different applications. The impact of such materials is directly related to our daily life from health, wealth, energy and environment. In this direction, CSIR-NPL is designing new materials to indigenize the several new technologies such as luminescent security ink to curb against counterfeiting of passport, Indian currency note and protect secrete documents, carbon materials for fuel cell and battery applications, carbon composite fuel tubes for nuclear reactor applications, carbon fibre polymer composite to replace steel Ilizarov fixator for biomedical applications, lightweight carbon nanotubes polymer composites as EMI shielding materials etc. Moreover, in spite of this, CSIR-NPL is also developing the different technologies to manage the reuse of plastic, electronic, PV module and agriculture waste to ensure safeguard of environment and fully recycling of material for the societal applications. Hence, the central aim of CSIR-NPL is to design and develop the materials with metrological grade to convert into all laboratory research invention to innovation, which will directly help all industrial sectors to promote their quality products with world class infrastructure.

Microorganisms have adapted different strategies to evolve according to the plant environment and interact either beneficially or detrimentally. The detrimental interactions include those with pathogenic viruses, bacteria, fungi, and pests. There have been more than 50,000 plant diseases reported. They impart major damage to world crop production. Chemical treatments have been widely used to control plant diseases; however, most of them present serious concerns for the environment and consumer health. With extensive research, various strategies have been developed to improve plant defense and provide resistance against pathogens. Marker-assisted molecular breeding and modern biotechnological approaches such as CRISPR-Cas, RNAi, etc., have extended greater promise in this regard. In addition, ecofriendly alternatives such as biological control agents have shown high potential for sustainable disease management. In this chapter, we elaborate various modern approaches used for the control and management of various diseases.

We report an enhancement in the thermoelectric performance of Cu2SnSe3 alloy on Pb doping, owing to a sharp increase in its power factor. The powder XRD pattern of all samples of Cu2Sn1−xPbxSe3 (0≤x≤0.03), prepared using solid state reaction, exhibited a cubic structure with a space group of F43m. The results show that temperature dependent electrical resistivity, ρ(T) increases with increasing temperature thereby demonstrating that the samples display heavily doped semiconducting nature, which could be satisfactorily described by small polaron hopping model in the whole temperature range of measurement for all the samples. Both the resistivity and the Seebeck coefficient are reduced with 2 vol% Pb doping. The thermal conductivity of all the samples reduces with increasing temperature. Despite a decrease in Seebeck coefficient the power factor shows an increase on Pb doping, owing to a sharp surge in the electrical conductivity which results in an enhanced ZTmax ~0.64 at 700 K for an optimized composition of Cu2Sn0.98Pb0.02Se3, which is nearly twice the value of the corresponding undoped counterpart.

Phytopathogens have evolved mechanisms to utilize host genes (commonly known as susceptibility factors) to promote their pathogenesis.

Tin selenide (SnSe) based thermoelectric materials are being explored for making inexpensive and efficient thermoelectric devices with improved thermoelectric efficiency. As both Sn and Se are earth abundant and relatively inexpensive and these alloys do not involve toxic materials, such as lead and expensive tellurium. Hence, in the present study, we have synthesized SnSe doped with 2 at% of aluminium (Al), lead (Pb), indium (In) and copper (Cu) individually, which is not reported in literature. Out of these, Cu doped SnSe resulted in enhancement of figure-of-merit (zT) of ∼0.7 ± 0.02 at 773 K, synthesized employing conventional fusion method followed by spark plasma sintering. This enhancement in zT is ∼16% over the existing state-of-the-art value for p-type SnSe alloy doped with expensive Ag. This enhancement in ZT is primarily due to the presence of Cu 2 Se second phase associated with intrinsic nanostructure formation of SnSe. This enhancement has been corroborated with the microstructural characterization using field emission scanning electron microscopy and X-ray diffraction studies. Also, Cu doped SnSe exhibited a higher value of carrier concentration in comparison to other samples doped with Al, Pb and In. Further, the compatibility factor of Cu doped SnSe alloys exhibited value of 1.62 V −1 at 773 K and it is suitable to segment with most of the novel TE materials for obtaining the higher thermoelectric efficiencies.

Motivated by the unprecedented thermoelectric performance of SnSe, we report its band structure calculations, based on density functional theory using the full potential linearized augmented plane wave. These calculations were further extended to evaluate the electrical transport properties using Boltzmann transport theory and the results were compared with the as-synthesized polycrystalline counterpart, which was synthesized employing conventional vacuum melting technique followed by consolidation employing spark plasma sintering. The as-synthesized SnSe was thoroughly characterized employing XRD, FESEM and TEM for phase purity, morphology and structure. The theoretically predicted band gap values and the temperature dependence of the electrical transport properties of SnSe were in reasonable agreement with the experimental results, within the approximations employed in our theoretical calculations. These theoretical calculations suggested that the optimum thermoelectric performance in SnSe is expected to occur at a hole doping concentration of ∼3 to 5 × 1021 cm−3. The measured fracture toughness and hardness of SnSe were found to be ∼0.76 ± 0.05 MPa √m and 0.27 ± 0.05 GPa, respectively, which are comparable with other state-of-the-art thermoelectric materials. The high value of thermal shock resistance ∼252 ± 9 W m−1, coupled with its good mechanical properties suggests SnSe to be a potential material for thermoelectric device applications.

In this study, we report low and mid temperature range thermoelectric properties of Sb-substituted Cu2SnSe3 compounds. The Cu2Sn1−xSbxSe3 (0 ≤ x ≤ 0.04) alloys were prepared using conventional solid-state reaction followed by spark plasma sintering. The crystal structure was characterized using XRD and it reveals that all the samples exhibit cubic structure with space group $$\stackrel{-}{4}3m$$. The electrical transport characteristics indicate degenerate semiconducting behavior. Electrical resistivity was found to follow small polaron hopping (SPH) model in the entire temperature range of investigation. The Seebeck coefficient data reveals that the majority of charge carriers are holes and the analysis of Seebeck coefficient data gives negative values of Fermi energy indicating that the Fermi energy is below the edge of valence band. The electronic contribution (κe) for total thermal conductivity is found to be less than 1%. The maximum ZT value of 0.64 is observed for the sample with x = 0.03 (at 700 K) which is approximately 2.3 times that of the pristine sample.

A new rare-earth-free NaZnPO4:Mn(2+) (NZP:Mn) phosphor powder has been developed by our group and investigated meticulously for the first time using secondary ion mass spectroscopy and chemical imaging techniques. The studies confirmed the effective incorporation of Mn(2+) into the host lattice, resulting in an enhancement of photoluminescence intensity. Phase purity has been verified and structure parameters have been determined successfully by Rietveld refinement studies. The NZP:Mn phosphor powder exhibits strong absorption bands in the ultraviolet and visible (300-470 nm) regions with a significant broad yellow-green (~543 nm) emission due to the characteristic spin forbidden d-d transition ((4)T1→(6)A1) of Mn(2+) ions, indicating weak crystal field strength at the zinc-replaced manganese site. The decay constants are a few milliseconds, which is a pre-requisite for applications in many display devices. The results obtained suggest that this new phosphor powder will find many interesting applications in semiconductor physics, as cost-effective light-emitting diodes (LEDs), as solar cells and in photo-physics.

We report the thermoelectric properties of nanostructured Cu-deficient Cu2Se, which was synthesized by high energy ball milling followed by spark plasma sintering. Our method obtained a significant enhancement in the thermoelectric figure of merit (ZT), i.e., ~1.4 at 973 K, which was ~30% higher than its bulk counterpart. This enhancement in the thermoelectric performance was due mainly to a significant reduction in the lattice thermal conductivity, which was attributed to enhanced phonon scattering at various length scales by nanoscale defects as well as abundant nanograin boundaries. The nanoscale defects were characterized by transmission electron microscopy of the nanostructured Cu2−xSe samples, which formed the basis of the ZT enhancement.

We report a simple experimental strategy for enhancing the figure-of-merit (ZT) of thermoelectric materials by introducing different kinds of defect features, including nano-porosity, in a range of nano to meso-scale dimensions, employing spark plasma assisted (SPS) reaction sintering of mechanically alloyed nanopowders. This strategy has been experimentally demonstrated in a well known thermoelectric compound, Cu2Se, which is shown to yield a high ZT of 2.1 at 973 K, which is among the highest reported value for this material and shows ~40% increase over its bulk melt-processed counterpart. The main contribution to the enhanced ZT, despite moderate values of power factor, primarily originates from a very small value of thermal conductivity of 0.34 W m−1 K−1. This low thermal conductivity owes its origin primarily to the enhanced low-to-high wavelength phonon scattering by different kinds of defects, in a wide spectrum of nano to meso-scale dimensions, involving microstructural defects generated during high-energy ball milling, abundant nanocrystalline grain boundaries due to very low crystallite size, and more importantly the nano-to-meso scale residual porosity created due to SPS at optimized process parameters. The role of SPS in enhancing the ZT has been discussed and this strategy can also be applied to other thermoelectric materials.

Copper selenide (Cu2Se) based materials are currently being investigated globally for efficient photovoltaic and thermoelectric (TE) device applications. Despite having enormous device potential its crystal structure and mechanical properties are still not fully explored owing to its complex behavior. Stereographic projection is one of such useful tools to estimate the crystallography of the material conclusively. In the current study, the crystal structure of α and β-phases of Cu2Se was determined by its stereographic projections in reciprocal space. Further, mechanical properties of Cu2Se are highly important to avoid catastrophic failure and ensure longevity of the TE devices made out of these materials. Cu2Se exhibited the compressive strength of ~45 MPa with ~3% of plastic strain and a fracture toughness value of ~2±0.02 MPa√m, the latter being significantly higher than that of the other known TE materials. Finally, thermal shock resistance, which is one of the crucial parameters for the stability and longevity of the device applications, was calculated to be ~281±12 W m−1. Superior mechanical properties coupled with highly reported thermoelectric behavior makes Cu2Se as a potential candidate for green energy generation.

BACKGROUND Plasmodium vivax synthesizes the largest number of 36 tryptophan-rich proteins belonging to the Pv-fam-a family. These parasite proteins need to be characterized for their biological function because tryptophan-rich proteins from other Plasmodium species have been proposed as vaccine candidates. METHODS Recombinant P. vivax tryptophan-rich antigens (PvTRAgs) were used to determine their erythrocyte-binding activity by a cell-based enzyme-linked immunosorbent assay, flow cytometry, and a rosetting assay. RESULTS Only 4 (PvTRAg26.3, PvTRAg34, PvTRAg36, and PvTRAg36.6) of 21 PvTRAgs bind to host erythrocytes. The cross-competition data indicated that PvTRAg36 and PvTRAg34 share their erythrocyte receptors with previously described proteins PvTRAg38 and PvTRAg33.5, respectively. On the other hand, PvTRAg26.3 and PvTRAg36.6 cross-compete with each other and not with any other PvTRAg, indicating that these 2 proteins bind to the same but yet another set of erythrocyte receptor(s). Together, 10 of 36 PvTRAgs possess erythrocyte-binding activity in which each protein recognizes >1 erythrocyte receptor. Further, each erythrocyte receptor is shared by >1 PvTRAg. CONCLUSIONS This redundancy may be useful for the parasite to invade red blood cells and cause disease pathogenesis, and it can be exploited to develop therapeutics against P. vivax malaria.

In the present communication, measurements of transition temperature, thermal conductivity, thermoelectric power and specific heat have been carried out on pristine and co-doped samples of Dy 0.95 Pr 0.05 Ba 2 (Cu 0.98 M 0.02 ) 3 O 7− δ system [M=Fe, Co, Ni and Zn]. The electrical resistivity results show that all the samples exhibit metallic behavior. The thermal conductivity results illustrate that for pristine sample of DyBa 2 Cu 3 O 7− δ , the expected pronounced hump in thermal conductivity is seen below the transition temperature. The hump is suppressed with 5% Pr-doping and this is further suppressed with co-doping. The thermoelectric power measurements show that the pristine sample exhibits hole-like behavior and this continues for doped as well co-doped samples. Pristine sample shows the expected jump in specific heat and with Pr-doping a slope change is observed near the transition temperature.

We report significant enhancement of the thermoelectric figure-of-merit of Mg2Si by double-doping with a combination of Bi, Pb, and Sb as doping elements. Addition of any two of these three elements to Mg2Si increases the electrical conductivity by more than three orders of magnitude at 323 K, irrespective of the doping elements used. However, a corresponding decrease in the Seebeck coefficient is observed in comparison with undoped Mg2Si. Irrespective of the combination of the three elements used for double doping, a figure-of-merit of approximately 0.7 at 873 K is obtained for Mg2Si; this is primarily because of enhancement of the electrical conductivity.

We report the synthesis, characterization and evaluation of the thermoelectric properties of Cu3SbSe3 with a view to explore its utility as an useful thermoelectric material due to its intrinsically low thermal conductivity. Cu3SbSe3 was synthesized employing a solid state reaction process followed by spark plasma sintering, and the synthesized material was extensively characterized for its phase, composition and structure, which suggested formation of a single-phase. The measured electrical transport properties of Cu3SbSe3 indicated p-type conduction in this material. The electrical transport behavior agrees well with that predicted theoretically using first-principle density-functional theory calculations, employing generalized gradient approximation. The measured thermal conductivity was found to be 0.26 W m−1 K−1 at 550 K, which is the lowest reported thus far for Cu3SbSe3 and is among the lowest for state-of-the-art thermoelectric materials. Despite its ultralow thermal conductivity coupled with a moderate Seebeck coefficient, the calculated value of its thermoelectric figure-of-merit was found to be exceptionally low (

Copper selenide (Cu2Se) is a simple binary compound which exhibits very fascinating thermoelectric properties, due to which it has been widely studied till very recently. This work highlights that the doping in Cu2Se only affect the electronic transport while the thermal transport is not significantly influenced due to the liquid like dynamics of the Cu ions in the lattice that results in significant thermal instabilities to an extent that the effect of doping is negligible. Our experiments show that an enhanced ZT ~1.6 at 860 K was achieved in Mg-doped Cu2Se, synthesized employing a facile single-step reactive spark plasma sintering technique, which is both fast and scalable. The experimental results indicate that Mg-doping in Cu2Se leads to a significant enhancement in its electrical conductivity, which is primarily responsible for the significant improvement in the ZT. However, the lattice thermal conductivity was found to remain relatively unchanged, irrespective of the Mg-doping concentration, which is also in agreement with our DFT calculations.

Plasmodium vivax is most wide spread and a neglected malaria parasite. There is a lack of information on parasite biology of this species. Genome of this parasite encodes for the largest number of tryptophan-rich proteins belonging to ‘Pv-fam-a’ family and some of them are potential drug/vaccine targets but their functional role(s) largely remains unexplored. Using bacterial and yeast two hybrid systems, we have identified the interacting partners for two of the P. vivax tryptophan-rich antigens called PvTRAg36.6 and PvTRAg56.2. The PvTRAg36.6 interacts with early transcribed membrane protein (ETRAMP) of P.vivax. It is apically localized in merozoites but in early stages it is seen in parasite periphery suggesting its likely involvement in parasitophorous vacuole membrane (PVM) development or maintenance. On the other hand, PvTRAg56.2 interacts with P.vivax merozoite surface protein7 (PvMSP7) and is localized on merozoite surface. Co-localization of PvTRAg56.2 with PvMSP1 and its molecular interaction with PvMSP7 probably suggest that, PvTRAg56.2 is part of MSP-complex, and might assist or stabilize the protein complex at the merozoite surface. In conclusion, the PvTRAg proteins have different sub cellular localizations and specific associated functions during intra-erythrocytic developmental cycle.

Nanoporous crack free alumina thin films were fabricated in two phases gamma (γ) and alpha (α) by sol–gel dip coating method. The thickness of the mesoporous films was increased with binder by varying its concentration, and with increasing the number of coating. The porosity, pore size, surface area and phase were controlled by sintering temperature. Interconnected pore structure of 8–15 nm diameter were successfully prepared by repeating the deposition several times. FESEM, BET, AFM and XRD techniques were employed for the microstructural characterization.

Despite SiGe being one of the most widely studied thermoelectric materials owing to its application in radioisotope thermoelectric generators (RTG), the thermoelectric figure-of merit (ZT) of p-type SiGe is still quite low, resulting in poor device efficiencies. In the present study, we report a substantial enhancement in ZT∼ 1.2 at 900 °C for p-type nanostructured Si80Ge20 alloys by creating several types of defect features within the Si80Ge20 nanostructured matrix in a spectrum of nano to meso-scale dimensions during its nanostructuring, by employing mechanical alloying followed by spark plasma sintering. This enhancement in ZT, which is ∼25% over the existing state-of-the-art value for a p-type nanostructured Si80Ge20 alloy, is primarily due to its ultralow thermal conductivity of ∼2.04 W m(-1) K(-1) at 900 °C, resulting from the scattering of low-to-high wavelength heat-carrying phonons by different types of defect features in a range of nano to meso-scale dimensions in the Si80Ge20 nanostructured matrix. These include point defects, dislocations, isolated amorphous regions, nano-scale grain boundaries and more importantly, the nano to meso-scale residual porosity distributed throughout the Si80Ge20 matrix. These nanoscale multi-dimensional defect features have been characterized by employing scanning and transmission electron microscopy and correlated with the electrical and thermal transport properties, based on which the enhancement of ZT has been discussed.

A new rare-earth-free NaZnPO4:Mn(2+) (NZP:Mn) phosphor powder has been developed by our group and investigated meticulously for the first time using secondary ion mass spectroscopy and chemical imaging techniques. The studies confirmed the effective incorporation of Mn(2+) into the host lattice, resulting in an enhancement of photoluminescence intensity. Phase purity has been verified and structure parameters have been determined successfully by Rietveld refinement studies. The NZP:Mn phosphor powder exhibits strong absorption bands in the ultraviolet and visible (300-470 nm) regions with a significant broad yellow-green (~543 nm) emission due to the characteristic spin forbidden d-d transition ((4)T1→(6)A1) of Mn(2+) ions, indicating weak crystal field strength at the zinc-replaced manganese site. The decay constants are a few milliseconds, which is a pre-requisite for applications in many display devices. The results obtained suggest that this new phosphor powder will find many interesting applications in semiconductor physics, as cost-effective light-emitting diodes (LEDs), as solar cells and in photo-physics.

Tryptophan-rich proteins play important biological functions for the Plasmodium parasite. Plasmodium vivax contains remarkably large numbers of such proteins belonging to the “Pv-fam-a” family that need to be characterized. Earlier, we reported the presence of memory T cells and naturally acquired antibodies against 15 of these proteins in P. vivax malaria-exposed individuals (M. Zeeshan, H. Bora, and Y. D. Sharma, J Infect Dis 207: 175–185, 2013, http://dx.doi.org/10.1093/infdis/jis650 ). Here, we sought to characterize and ascertain the cross talk between effector responses of T and B cells in malarial patients against all Pv-fam-a family proteins. Therefore, we expressed the remaining 21 of these proteins in Escherichia coli and studied the humoral and cellular immune responses based on the same parameters used in our previous study. Naturally acquired IgG antibodies were detected against all 21 antigens in P. vivax patient sera (37.7 to 94.4% seropositivity). These antigens were able to activate the lymphocytes of P. vivax -exposed individuals, and the activated CD4 + T lymphocytes produced higher levels of Th1 (interleukin-2 [IL-2] and gamma interferon [IFN-γ]) and Th2 (IL-4 and IL-10) cytokines than the healthy controls, but the response was Th2 biased. The combined results of present and previous studies seem to suggest a striking link between induction of the CD4 + T cell response and naturally acquired antibodies against all 36 proteins of the Pv-fam-a family, the majority of them having conserved sequences in the parasite population. Further work is required to utilize this information to develop immunotherapeutic treatments for this disease.

Bulk SnSe is reported to be an excellent thermoelectric material at high temperatures. We now present the results on thermoelectric properties of nanoribbons of SnSe of variable widths obtained using density functional theory coupled with semi-classical Boltzmann theory. The calculated results find armchair nanoribbons of width

We report the band structure calculations for high temperature cubic phase of copper selenide (Cu2Se) employing Hartree-Fock approximation using density functional theory within the generalized gradient approximation. These calculations were further extended to theoretically estimate the electrical transport coefficients of Cu2Se employing Boltzmann transport theory, which show a reasonable agreement with the corresponding experimentally measured values. The calculated transport coefficients are discussed in terms of the thermoelectric (TE) performance of this material, which suggests that Cu2Se can be a potential p-type TE material with an optimum TE performance at a carrier concentration of ∼ 4−6×1021cm−3.

Owing to their high thermoelectric (TE) figure-of-merit, nanostructured Si80Ge20 alloys are evolving as a potential replacement for their bulk counterparts in designing efficient radio-isotope TE generators. However, as the mechanical properties of these alloys are equally important in order to avoid in-service catastrophic failure of their TE modules, we report the strength, hardness, fracture toughness, and thermal shock resistance of nanostructured n-type Si80Ge20 alloys synthesized employing spark plasma sintering of mechanically alloyed nanopowders of its constituent elements. These mechanical properties show a significant enhancement, which has been correlated with the microstructural features at nano-scale, delineated by transmission electron microscopy.

The direct reaction between [{Pd(μ-AcO)(CˆP)}2] 1 and cyclic imides to yield new dinuclear cyclometallated palladium(II) complexes containing –NCO– bridging imidates of general formula [{Pd(μ-NCO)(CˆP)}2] (CˆP = CH2C6H4P(o-tolyl)2; –NCO– = succinimidate (suc) 2, maleimidate (mal) 3, phthalimidate (phthal) 4 or saccharinate (sacc) 5 is described. Spectroscopic techniques and structural characterisation by X-ray diffraction of complex 2 confirmed the proposed formulae. The new dimeric complexes are shown to be excellent catalysts for the selective formylation of aryl halides under CO-free conditions to obtain synthetically important aromatic aldehydes. Yields are diminished by steric hindrance around the aryl halides.