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[en] It is well-known that a strand burner is an apparatus that provides burning rate measurements of a solid propellant at an elevated pressure in order to obtain the burning characteristics of a propellant. This paper describes the facilities developed by author that was used in his studies. The burning rate characteristics of solid propellant have be evaluated over five different chamber pressures ranging from 1 atm to 31 atm using a strand burner. The strand burner has a mounting stand that allows the propellant strand to be mounted vertically. The strand was ignited electrically using hot wire, and the burning time was recorded by electronic timer. Wire technique was used to measure the burning rate. Preliminary results from these techniques are presented. This study shows that the strand burner can be used on propellant strands to obtain accurate low pressure burning rate data
[en] A brief review of the methods of combustion of low-reaction solid fuel is presented. The advantages and the drawbacks of these methods are assessed. Their applications are discussed. The advantages of solid fuel combustion by using the fluidized bed are justified. (author)
[en] Glassy solid electrolytes have large potential for a number of electrochemical applications, the most important among them being the solid state batteries. In order to successfully accomplish these applications it is necessary to have a background of the science and technology of glassy solid electrolytes. This paper gives a brief account of the formation of glassy solid electrolytes, factors affecting ionic conductivity in these materials. Typical results have been discussed to get some insight into the glassy solid electrolytes. The status of lithium battery involving lithium conducting glasses and the challenges in its development have been highlighted.
[en] All-solid-state lithium/sulfur (Li/S) battery is prepared using siloxane cross-linked network solid electrolyte at room temperature. The solid electrolytes show high ionic conductivity and good electrochemical stability with lithium and sulfur. In the first discharge curve, all-solid-state Li/S battery shows three plateau potential regions of 2.4 V, 2.12 V and 2.00 V, respectively. The battery shows the first discharge capacity of 1044 mAh g−1-sulfur at room temperature. This first discharge capacity rapidly decreases in 4th cycle and remains at 512 mAh g−1-sulfur after 10 cycles.
[en] Planar waveguide laser has been one of the most promising high power solid-state lasers, due to its outstanding performance in terms of large mode volume and one dimension being confined. The current status and future perspectives of planar waveguide lasers at home and abroad are reviewed. Some attractive structures of planar waveguides are compared and discussed in detail, including double-clad waveguide configuration, the tapered structure waveguide and the self-imaging structure. The advancements of high power planar waveguide lasers as well as some limitations are analyzed. (authors)
[en] For power generation, fuel cells offer a number of advantages over conventional thermal power stations such as high efficiency, low pollution and CO2 emissions and the ability to be used as distributed power generation sources at load centres. Amongst these, the direct carbon fuel cell (DCFC) offers many additional attributes which include near 100% fuel utilisation, 100% theoretical efficiency and almost pure CO2 in the flue stream requiring no costly separation from other gases. In the solid oxide electrolyte based DCFC, for effective oxidation of solid fuel, the anode plays a significant role. In particular, the mixed ionic electronic conducting ceramics offer the potential of shifting reaction sites from anode/electrolyte interface to fuel/anode interface thus making it easier for oxidation of solid fuel which unlike gaseous fuels cannot penetrate in the porous structure of the anode. In this paper, in view of a good mix of ionic and electronic conductivity and the possibility of higher catalytic activity of Co doped lanthanum strontium titanates for hydrocarbon fuel oxidation, these materials have been investigated as a potential anode for use in a DCFC. The performance was evaluated with solid carbon, H2 and CO as fuel feeds. The performance has been compared with Sr0.86Y0.08TiO3 and La0.3Sr0.7TiO3. The effect of adding a noble metal catalyst in small quantities has also been reported to facilitate the carbon oxidation reaction
[en] It is the Proceeding of the 8th national conference on Solid State Nuclear Track detectors. 41 theses are collected in this proceedings. The new development and application in China is introduced
[en] An efficient density functional algorithm (DFA) that scales linearly with system size will revolutionize electronic structure calculations. Density functional calculations are reliable and accurate in determining many condensed matter and molecular ground-state properties. However, because current DFA's, including methods related to that of Car and Parrinello, scale with the cube of the system size, density functional studies are not routinely applied to large systems. Linear scaling is achieved by constructing functions that are both localized and fully occupied, thereby eliminating the need to calculate global eigenfunctions. It is, however, widely believed that exponential localization requires the existence of an energy gap between the occupied and unoccupied states. Despite this, the authors demonstrate that linear scaling can still be achieved for metals. Using a linear scaling algorithm, they have explicitly constructed localized, almost fully occupied orbitals for the quintessential metallic system, jellium. The algorithm is readily generalizable to any system geometry and Hamiltonian. They will discuss the conceptual issues involved, convergence properties and scaling for their new algorithm