Synergistic effect of SiO2 on proton conduction and thermal behavior for nanocomposite electrolyte CsH2PO4 fuel cells

Journal of Materials Science: Materials in Electronics - Solid acid composite electrolytes (1?x)CsH2PO4(CDP)/xSiO2 (0?≤?x?≤?0.35) were prepared and...     

Zwitterion-assisted transition metal dichalcogenide nanosheets for scalable and biocompatible inkjet printing

Nano Research - Inkjet printing of two-dimensional (2D) transition metal dichalcogenide (TMD) nanosheets fabricated by liquid-phase exfoliation (LPE) allows simple, mass-producible, and low-cost...     

Flexible supercapacitor based on three‐dimensional cellulose/graphite/polyaniline composite

Fast charge‐discharge rate and high areal capacitance, along with high mechanically stability, are the pre‐requisites for flexible supercapacitors to power flexible electronic devices. In this paper, we have used three‐dimensional polyacrylonitrile graphite foam as flexible current collector for electro‐deposition of polyaniline (PANI) nanowires. The graphite foam with PANI was then used to fabricate symmetric supercapacitor. The fabricated supercapacitor in the three‐electrode system shows a high specific capacitance (C_sp) of 357 F.g^?1 and areal capacitance (C_areal) of 7142 mF.cm^?2 in 1 M H₂SO₄ at current density of 80 mA.cm^?2, while using two‐electrode system, it shows C_sp of 256 F.g^?1 and C_areal of 5120 mF.cm^?2 in 1 M H₂SO₄ at current density of 100 mA.cm^?2. The current density of 100 mA.cm^?2 is up to 10 folds higher than reported current densities of many PANI‐based supercapacitors. The high capacitance can be attributed to the spongy network of PANI‐NWs on three‐dimensional graphite surface which provides an easy path for electrolyte ions in active electrode materials. The developed supercapacitor shows specific energy of 64.8 Whkg^?1 and a specific power of 6.1 kWkg^?1 with a marginally decrease of 1.6% in C_sp after 1000^th cycles, along with coulombic efficiency retention of 87% in polyvinyl alcohol/H₂SO₄ gel electrolyte. This flexible supercapacitor exhibits great potential for energy storage application.     

Scientific Perceptions and Community Responses in a Participatory Water Management Endeavor

People and technology are the two major ingredients considered to enhance benefits and provide opportunities in farming system. Perfect blending of these ingredients not only leads to maximize the agricultural production but also helps in improving livelihood. Openhanded efforts have been initiated to understand farm resources, production constraints and support services in order to suggest need based and cost effective technologies/practices, which can be adopted by the farmers employing participatory approach without or least financial incentivization. This approach is in contrast to earlier approaches where quality inputs and incentives are provided by project implementing agencies to promote technologies/practices. As in the earlier approach the farmer’s involvement in planning and implementation is poor, introduction of participatory process and technologies/practices remains no longer sustainable and once the financial support from the project area is withdrawn farmers’ follow the same age old traditional practices. This led to realization that perspectives of local people’s needs to be in the center of development, research and extension efforts, if substantial impact is to be made. The objective of this paper is to share the experiences of a multi disciplinary and multi institutional participatory approach undertaken, in ICAR-DFID collaborative project in India, to improve livelihood of community including poorest of the poor through integrated land and water management. The purpose here is to establish a more differentiated communication and a conceptual framework, which can help researchers and practitioners to make better choices and more informed decisions when designing their research, communication and dissemination approaches.     

Progress Towards an Optimization Methodology for Combustion-Driven Portable Thermoelectric Power Generation Systems

There is enormous military and commercial interest in developing quiet, lightweight, and compact thermoelectric (TE) power generation systems. This paper investigates design integration and analysis of an advanced TE power generation system implementing JP-8 fueled combustion and thermal recuperation. In the design and development of this portable TE power system using a JP-8 combustor as a high-temperature heat source, optimal process flows depend on efficient heat generation, transfer, and recovery within the system. The combustor performance and TE subsystem performance were coupled directly through combustor exhaust temperatures, fuel and air mass flow rates, heat exchanger performance, subsequent hot-side temperatures, and cold-side cooling techniques and temperatures. Systematic investigation and design optimization of this TE power system relied on accurate thermodynamic modeling of complex, high-temperature combustion processes concomitantly with detailed TE converter thermal/mechanical modeling. To this end, this paper reports integration of system-level process flow simulations using CHEMCAD? commercial software with in-house TE converter and module optimization, and heat exchanger analyses using COMSOL? software. High-performance, high-temperature TE materials and segmented TE element designs are incorporated in coupled design analyses to achieve predicted TE subsystem-level conversion efficiencies exceeding 10%. These TE advances are integrated with a high-performance microtechnology combustion reactor based on recent advances at Pacific Northwest National Laboratory (PNNL). Predictions from this coupled simulation approach lead directly to system efficiency?Cpower maps defining potentially available optimal system operating conditions and regimes. Further, it is shown that, for a given fuel flow rate, there exists a combination of recuperative effectiveness and hot-side heat exchanger effectiveness that provides a higher specific power output from the TE modules. This coupled simulation approach enables pathways for integrated use of high-performance combustor components, high-performance TE devices, and microtechnologies to produce a compact, lightweight, combustion-driven TE power system prototype that operates on common fuels.     

Carbon dioxide: a renewable feedstock for the synthesis of fine and bulk chemicals

The syntheses of carbon dioxide (CO₂) based industrially important chemicals have gained considerable interest in view of the sustainable chemistry and “green chemistry” concepts. In this review, recent developments in the chemical fixation of CO₂ to valuable chemicals are discussed. The synthesis of five-member cyclic carbonates via, cycloaddition of CO₂ to epoxides is one of the promising reactions replacing the existing poisonous phosgene-based synthetic route. This review focuses on the synthesis of cyclic carbonates, vinyl carbamates, and quinazoline-2,4(1H,3H)-diones via reaction of CO₂ and epoxide, amines/phenyl acetylene, 2-aminobenzinitrile and other chemicals. Direct synthesis of dimethyl carbonate, 1,3-disubstituted urea and 2-oxazolidinones/2-imidazolidinones have limitations at present because of the reaction equilibrium and chemical inertness of CO₂. The preferred alternatives for their synthesis like transesterification of ethylene carbonate with methanol, transamination of ethylene carbonate with primary amine and transamination reaction of ethylene carbonate with diamines/β-aminoalcohols are discussed. These methodologies offer marked improvements for greener chemical fixation of CO₂ in to industrially important chemicals.     

The who, what, why, where, and when of IT outsourcing

Outsourcing of IT functions has become so pervasive that IT managers and CIOs cannot ignore it. To complicate the matter, outsourcing to other countries has become increasingly popular. The advantages of this type of outsourcing include cost savings, 24/7 operation, and access to highly specialized skills. Yet a strategic alliance with a geographically and culturally remote partner presents its own unique challenges. Thus, IT professionals should not take the strategic questions of whether or not to outsource lightly, or avoid it. Rather, they can make such a decision by analyzing the responses to the following five key questions, what we call the five Ws: Who should outsource? What is outsourcing? Why outsource? Where should you outsource? When should you outsource? This article emerged from a focus group of CIOs conducted by the CIO Institute, a not-for-profit community of practice for CIOs in the Greater Philadelphia region.