Modern energy access to all in rural India: An integrated implementation strategy

Expanding energy access to the rural population of India presents a critical challenge for its government. The presence of 364 million people without access to electricity and 726 million who rely on biomass for cooking indicate both the failure of past policies and programs, and the need for a radical redesign of the current system. We propose an integrated implementation framework with recommendations for adopting business principles with innovative institutional, regulatory, financing and delivery mechanisms. The framework entails establishment of rural energy access authorities and energy access funds, both at the national and regional levels, to be empowered with enabling regulatory policies, capital resources and the support of multi-stakeholder partnership. These institutions are expected to design, lead, manage and monitor the rural energy interventions. At the other end, trained entrepreneurs would be expected to establish bioenergy-based micro-enterprises that will produce and distribute energy carriers to rural households at an affordable cost. The ESCOs will function as intermediaries between these enterprises and the international carbon market both in aggregating carbon credits and in trading them under CDM. If implemented, such a program could address the challenges of rural energy empowerment by creating access to modern energy carriers and climate change mitigation. (C) 2011 Elsevier Ltd. All rights reserved.

Full spin and spatial symmetry adapted technique for correlated electronic hamiltonians: Application to an icosahedral cluster

One of the long standing problems in quantum chemistry had been the inability to exploit full spatial and spin symmetry of an electronic Hamiltonian belonging to a non-Abelian point group. Here, we present a general technique which can utilize all the symmetries of an electronic (magnetic) Hamiltonian to obtain its full eigenvalue spectrum. This is a hybrid method based on Valence Bond basis and the basis of constant z-component of the total spin. This technique is applicable to systems with any point group symmetry and is easy to implement on a computer. We illustrate the power of the method by applying it to a model icosahedral half-filled electronic system. This model spans a huge Hilbert space (dimension 1,778,966) and in the largest non-Abelian point group. The C60 molecule has this symmetry and hence our calculation throw light on the higher energy excited states of the bucky ball. This method can also be utilized to study finite temperature properties of strongly correlated systems within an exact diagonalization approach. (C) 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012

15-deoxyspergualin hinders physical interaction between basic residues of transit peptide in PfENR and Hsp70-1

The apicoplast of Plasmodium harbors several metabolic pathways. The enzymes required to perform these reactions are all nuclearly encoded and apicoplast targeted (NEAT) proteins. Plasmodium falciparum Enoyl-ACP Reductase (PfENR) is one such NEAT protein. The NEAT proteins have a transit peptide which is required for crossing the membranes of apicoplast. We studied the importance of basic residues like Arginine and Lysine within the transit peptide. Previous studies have suggested that all basic residues are essential for apicoplast trafficking. In this study, we demonstrate that only some of these residues are essential (K44, R48, K51, and R52), whereas others are dispensable (R40, K42, and K49). On mutating these specific residues, PfENR is not imported into the apicoplast and is mislocalized to the cytoplasm. We also demonstrate that these residues are also crucial for interaction with Hsp70-1, implying that interactions of Lysine 44, Arginine 48, Lysine 51, and Arginine 52 of the transit peptide with PfHsp70-1 are required for apicoplast trafficking. 15-Deoxyspergualin, which has earlier been proposed to interact with EEVD motif of PfHsp70-1 hinders the physical interaction between these cationic residues of PfENR and Hsp70-1. Hence, we propose that in the transport competent state of NEAT proteins some specific positively charged amino acids in the transit peptide interact with PfHsp70-1, and this interaction is essential for apicoplast targeting.

Evaluation of physico-mechanical properties and in vitro biocompatibility of compression molded HDPE based biocomposites with HA/Al2O3 ceramic fillers and titanate coupling agents

The present article demonstrates how the stiffness, hardness as well as the cellular response of bioinert high-density polyethylene (HDPE) can be significantly improved with combined addition of both bioinert and bioactive ceramic fillers. For this purpose, different amounts of hydroxyapatite and alumina, limited to a total of 40 wt %, have been incorporated in HDPE matrix. An important step in composite fabrication was to select appropriate solvent and optimal addition of coupling agent (CA). In case of chemically coupled composites, 2% Titanium IV, 2-propanolato, tris iso-octadecanoato-O was used as a CA. All the hybrid composites, except monolithic HDPE, were fabricated under optimized compression molding condition (140 degrees C, 0.75 h, 10 MPa pressure). The compression molded composites were characterized, using X-ray diffraction, Fourier transformed infrared spectroscopy, and scanning electron microscopy. Importantly, in vitro cell culture and cell viability study (MTT) using L929 fibroblast and SaOS2 osteoblast-like cells confirmed good cytocompatibility properties of the developed hybrid composites. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Application of kinetic schemes to all types of meshes

Kinetic schemes as pursued in CFD Centre are obtained by taking suitable moments of upwind schemes for Boltzmann equation without collision term. The primary ones among these are KFVS, LSKUM, KFMG and these have been applied successfully to a variety of flow problems using various meshes. These schemes have been found to be very robust.

Durable Transition-Metal-Carbide-Supported Pt-Ru Anodes for Direct Methanol Fuel Cells

Molybdenum carbide (MoC) and tungsten carbide (WC) are synthesized by direct carbonization method. PtRu catalysts supported on MoC, WC, and Vulcan XC-72R are prepared, and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy in conjunction with electrochemistry. Electrochemical activities for the catalysts towards methanol electro-oxidation are studied by cyclic voltammetry. All the electro-catalysts are subjected to accelerated durability test (ADT). The electrochemical activity of carbide-supported electro-catalysts towards methanol electro-oxidation is found to be higher than carbon-supported catalysts before and after ADT. The study suggests that PtRu/MoC and PtRu/WC catalysts are more durable than PtRu/C. Direct methanol fuel cells (DMFCs) with PtRu/MoC and PtRu/WC anodes also exhibit higher performance than the DMFC with PtRu/C anode.

Analysis of oxide and vanadate supports for catalytic hydrogen combustion: Kinetic and mechanistic investigations

Combustion synthesized oxide and vanadate compounds (CeO2, Fe2O3, CeVO4, and FeVO4) were tested for catalytic hydrogen combustion. The compounds were characterized by X-ray diffraction and X-ray photoelectron spectroscopy. All the four compounds showed good activity and stability for catalytic hydrogen combustion and more than 95% conversion was observed over all the compounds within 500 degrees C. The mechanisms for the reaction over the different classes of compounds (cerium-based and iron-based compounds) were proposed on the basis of spectroscopic observations. The main difference in the mechanisms was in the nature of adsorption of H2 over the sites. The elementary processes for the reaction were proposed, corresponding rate expressions were derived, and the rate parameters for the reaction were estimated using nonlinear regression. Langmuir-Hinshelwood and Eley-Rideal mechanisms were also tested for the reaction and the proposed mechanism was compared with these mechanisms. (c) 2011 American Institute of Chemical Engineers AIChE J, 2012

Andaman Postseismic Deformation Observations: Still Slipping after All These Years?

More than six years after the great (M-w 9.2) Sumatra-Andaman earthquake, postevent processes responsible for relaxation of the coseismic stress change remain controversial. Modeling of Andaman Islands Global Positioning System (GPS) displacements indicated early near-field motions were dominated by slip down-dip of the rupture, but various researchers ascribe elements of relaxation to dominantly poroelastic, dominantly viscoelastic, and dominantly fault slip processes, depending primarily on their measurement sampling and modeling tools used. After subtracting a pre-2004 interseismic velocity, significant transient motion during the 2008.5-2010.5 epoch confirms that postseismic relaxation processes continue in Andaman. Modeling three-component velocities as viscoelastic flow yields a weighted root-mean-square (wrms) misfit that always exceeds the wrms of the measured signal (26.3 mm/yr). The best-fitting models are those that yield negligible deformation, indicating the model parameters have no real physical meaning. GPS velocities are well fit (wrms 4.0 mm/yr) by combining a viscoelastic flow model that best fits the horizontal velocities with similar to 50 cm/yr thrust slip down-dip of the coseismic rupture. Both deep slip and flow respond to stress changes, and each can significantly change stress in the realm of the other; it therefore is reasonable to expect that both transient deep slip and viscoelastic flow will influence surface deformation long after a great earthquake.

Dijet resonances, widths and all that

The search for heavy resonances in the dijet channel is part of the on-going physics programme, both at the Tevatron and at the LHC. Lower limits have been placed on the masses of dijet resonances predicted in a wide variety of models. However, across experiments, the search strategy assumes that the effect of the new particles is well-approximated by on-shell production and subsequent decay into a pair of jets. We examine the impact of off-shell effects on such searches, particularly for strongly interacting resonances.

Thermal instability and the feedback regulation of hot haloes in clusters, groups and galaxies

We present global multidimensional numerical simulations of the plasma that pervades the dark matter haloes of clusters, groups and massive galaxies (the intracluster medium; ICM). Observations of clusters and groups imply that such haloes are roughly in global thermal equilibrium, with heating balancing cooling when averaged over sufficiently long time- and length-scales; the ICM is, however, very likely to be locally thermally unstable. Using simple observationally motivated heating prescriptions, we show that local thermal instability (TI) can produce a multiphase medium with similar to 104 K cold filaments condensing out of the hot ICM only when the ratio of the TI time-scale in the hot plasma (tTI) to the free-fall time-scale (tff) satisfies tTI/tff? 10. This criterion quantitatively explains why cold gas and star formation are preferentially observed in low-entropy clusters and groups. In addition, the interplay among heating, cooling and TI reduces the net cooling rate and the mass accretion rate at small radii by factors of similar to 100 relative to cooling-flow models. This dramatic reduction is in line with observations. The feedback efficiency required to prevent a cooling flow is similar to 10-3 for clusters and decreases for lower mass haloes; supernova heating may be energetically sufficient to balance cooling in galactic haloes. We further argue that the ICM self-adjusts so that tTI/tff? 10 at all radii. When this criterion is not satisfied, cold filaments condense out of the hot phase and reduce the density of the ICM. These cold filaments can power the black hole and/or stellar feedback required for global thermal balance, which drives tTI/tff? 10. In comparison to clusters, groups have central cores with lower densities and larger radii. This can account for the deviations from self-similarity in the X-ray luminositytemperature () relation. The high-velocity clouds observed in the Galactic halo can be due to local TI producing multiphase gas close to the virial radius if the density of the hot plasma in the Galactic halo is >rsim 10-5 cm-3 at large radii.

Composites of Graphene and Other Nanocarbons with Organogelators Assembled through Supramolecular Interactions

Carbon nanomaterials (CNMs), such as exfoliated graphene (EG), long-chain functionalized EG, single-walled carbon nanotubes (SWNTs), and fullerene (C-60), have been investigated for their interaction with two structurally different gelators based on all-trans tri-p-phenylenevinylene bis-aldoxime (1) and n-lauroyl-L-alanine (2) both in solution and in supramolecular organogels. Gelation occurs in toluene through hydrogen bonding and van der Waals interactions for 1 and 2 in addition to pp stacking specifically in the case of 1. These nanocomposites provide a thorough understanding in terms of molecular-level interactions of dimensionally different CNMs with structurally different gelators. The presence of densely wrapped CNMs encapsulated fibrous network in the resulting composites is evident from various spectroscopic and microscopic studies, indicating the presence of supramolecular interactions. Concentration- and temperature-dependent UV/Vis and fluorescence spectra show that CNMs promote aggregation of the gelator molecules, leading to hypochromism and quenching of the fluorescence intensity. Thermotropic mesophases of 1 are altered by the inclusion of a small amount of CNMs. The gelCNM composites show increased electrical conductivity compared with that of the native organogel. Rheological studies of the composites demonstrate the formation of rigid and viscoelastic solidlike assembly due to reinforced aggregation of the gelators on CNMs. Synergistic behavior is observed in case of the composite gel of 1, containing a mixture of EG and SWNT, when compared with other mixtures of CNMs in all combinations with EG. This affords new nanocomposites with interesting optical, thermal, electrical, and mechanical properties.

Sliding-Mode Guidance and Control for All-Aspect Interceptors with Terminal Angle Constraints

In this paper, sliding-mode-control-based guidance laws to intercept stationary, constant-velocity, and maneuvering targets at a desired impact angle are proposed. The desired impact angle, which is defined in terms of a desired line-of-sight angle, is achieved in finite time by selecting the missile's lateral acceleration to enforce terminal sliding mode on a switching surface designed using nonlinear engagement dynamics. The conditions for capturability are also presented. In addition, by considering a three-degree-of-freedom linear-interceptor dynamic model and by following the procedure used to design a dynamic sliding-mode controller, the interceptor autopilot is designed as a simple static controller to track the lateral acceleration generated by the guidance law. Numerical simulation results are presented to validate the proposed guidance laws and the autopilot design for different initial engagement geometries and impact angles.

Dendrimer building toolkit: Model building and characterization of various dendrimer architectures

We have developed a graphical user interface based dendrimer builder toolkit (DBT) which can be used to generate the dendrimer configuration of desired generation for various dendrimer architectures. The validation of structures generated by this tool was carried out by studying the structural properties of two well known classes of dendrimers: ethylenediamine cored poly(amidoamine) (PAMAM) dendrimer, diaminobutyl cored poly(propylene imine) (PPI) dendrimer. Using full atomistic molecular dynamics (MD) simulation we have calculated the radius of gyration, shape tensor and monomer density distribution for PAMAM and PPI dendrimer at neutral and high pH. A good agreement between the available simulation and experimental (small angle X-ray and neutron scattering; SAXS, SANS) results and calculated radius of gyration was observed. With this validation we have used DBT to build another new class of nitrogen cored poly(propyl ether imine) dendrimer and study it's structural features using all atomistic MD simulation. DBT is a versatile tool and can be easily used to generate other dendrimer structures with different chemistry and topology. The use of general amber force field to describe the intra-molecular interactions allows us to integrate this tool easily with the widely used molecular dynamics software AMBER. This makes our tool a very useful utility which can help to facilitate the study of dendrimer interaction with nucleic acids, protein and lipid bilayer for various biological applications. (c) 2012 Wiley Periodicals, Inc.

A unified approach to known and unknown cases of Berge's conjecture

Berge's elegant dipath partition conjecture from 1982 states that in a dipath partition P of the vertex set of a digraph minimizing , there exists a collection Ck of k disjoint independent sets, where each dipath P?P meets exactly min{|P|, k} of the independent sets in C. This conjecture extends Linial's conjecture, the GreeneKleitman Theorem and Dilworth's Theorem for all digraphs. The conjecture is known to be true for acyclic digraphs. For general digraphs, it is known for k=1 by the GallaiMilgram Theorem, for k?? (where ?is the number of vertices in the longest dipath in the graph), by the GallaiRoy Theorem, and when the optimal path partition P contains only dipaths P with |P|?k. Recently, it was proved (Eur J Combin (2007)) for k=2. There was no proof that covers all the known cases of Berge's conjecture. In this article, we give an algorithmic proof of a stronger version of the conjecture for acyclic digraphs, using network flows, which covers all the known cases, except the case k=2, and the new, unknown case, of k=?-1 for all digraphs. So far, there has been no proof that unified all these cases. This proof gives hope for finding a proof for all k.

All flavours of El Nino have similar early subsurface origins

The El Nino/Southern Oscillation phenomenon, characterized by anomalous sea surface temperatures and winds in the tropical Pacific, affects climate across the globe(1). El Ninos occur every 2-7 years, whereas the El Nino/Southern Oscillation itself varies on decadal timescales in frequency and amplitude, with a different spatial pattern of surface anomalies(2) each time the tropical Pacific undergoes a regime shift. Recent work has shown that Bjerknes feedback(3,4) (coupling of the atmosphere and the ocean through changes in equatorial winds driven by changes in sea surface temperature owing to suppression of equatorial upwelling in the east Pacific) is not necessary(5) for the development of an El Nino. Thus it is unclear what remains constant through regimes and is crucial for producing the anomalies recognized as El Nino. Here we show that the subsurface process of discharging warm waters always begins in the boreal summer/autumn of the year before the event (up to 18 months before the peak) independent of regimes, identifying the discharge process as fundamental to the El Nino onset. It is therefore imperative that models capture this process accurately to further our theoretical understanding, improve forecasts and predict how the El Nino/Southern Oscillation may respond to climate change.