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In this paper, we report a turn-on fluorescence sensing of Al.sup.3+ ion using a new fluorenone derivative. The imino derivative of 2-amino-9-fluorenone and mercapto-2-butanone is synthesized and characterized using IR, NMR, and mass spectral techniques. The fluorescence of the compound shows a large enhancement at the addition of Al.sup.3+ ions, and other metal ions show insignificant changes of the fluorescence. The stoichiometry and the binding constant of the complex are reported. The detection limit of the Al.sup.3+ determination by the fluorenone derivative is 5 x 10.sup.-8 M. A visible enhancement of color occurs on illumination of the fluorescent compound - Al.sup.3+ ion complex., Author(s): S. E. Thangaraj [sup.1] , E. J. Antony [sup.1] , G. T. Selvan [sup.2] , P. M. Selvakumar [sup.2] , I. V. M. V. Enoch [sup.1] [sup.2] Author Affiliations: [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.comnet.2010.06.019 Byline: Yuan Rao (a)(b), Ru-chuan Wang (a) Keywords: Load balancing; Agent; Satellite networks; Routing Abstract: To ensure an intelligent engineering of traffic over entire satellite networks, a distributed routing scheme for low-earth orbit (LEO) satellite networks, agent-based load balancing routing (ALBR), is presented. Two kinds of agents are used. Mobile agents migrate autonomously to explore the path connecting source and destination, to gather inter-satellite link (ISL) cost, identifier and latitude of visited satellites. Meanwhile, stationary agents employ exponential forgetting function to estimate ISL queueing delay, calculate ISL cost using the sum of propagation and queueing delays; evaluate path cost considering satellite geographical position as well as ISL cost, finally update routing items. Through simulations on a Courier-like system, the proposed scheme is shown to achieve better load balancing, and can especially decrease packet loss ratio efficiently, guarantee better throughput and end-to-end delay bound in case of high traffic load. Furthermore, results from the implementation complexity analysis demonstrate that with the aid of agent technology, ALBR has lower on-board computation, storage, signaling requirements than other on-board routing schemes. Author Affiliation: (a) College of Computer, Nanjing University of Posts and Telecommunications, Nanjing 210003, China (b) College of Information and Computer, Anhui Agricultural University, Hefei 230036, China Article History: Received 11 September 2009; Revised 23 June 2010; Accepted 27 June 2010 Article Note: (miscellaneous) Responsible Editor: I.F. Akyildiz

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2010.06.001 Byline: P.K. Basu (a), R.M. Pujahari (a)(b), Harpreet Kaur (b)(c), Devi Singh (b), D. Varandani (d), B.R. Mehta (d) Keywords: Multicrystalline large area silicon solar cell; NaOH-NaOCl texturization; HF-HNO.sub.3-CH.sub.3COOH texturization; AFM study; Reflectivity study; Cell LIV and DIV characteristics Abstract: Sodium hydroxide (NaOH) and sodium hypochlorite (NaOCl) solution (1:1 ratio by volume) based texturization process at 80-82[degrees]C is an easy, low cost and comparatively new and convenient option for fabrication of any multicrystalline silicon (mC-Si) solar cell. In the present study atomic force microscope is used to observe the intragrain surface in a miniscule area (3[mu]mx3[mu]m) of NaOH-NaOCl textured surface by two and three dimensional analysis, roughness analysis and section analysis. The r.m.s value of the surface parameter of 7.0nm ascertains the smoothness of the textured surface and further the surface reflectivity is minimized to 4-6% in the 500-1000nm wavelength range by a proper silicon nitride anti-reflection coating. Comparing with the standard HF-HNO.sub.3-CH.sub.3COOH acid textured cell, the NaOH-NaOCl textured cell shows a comparatively lower value of series resistance of 7.17mI[c], higher value of shunt resistance of 18.4I[c] to yield a fill factor of 0.766 leading to more than 15% cell efficiency in the industrial cell processing line. This AFM study yields different surface roughness parameters for the NaOH-NaOCl textured wafers which can be used as a reference standard for optimized texturing. Author Affiliation: (a) Department of Physics, Echelon Institute of Technology, Faridabad 121002, Haryana, India (b) Department of Physics, Manav Rachna International University, Faridabad 121001, Haryana, India (c) Department of Physics, Advanced Institute of Technology and Management, Palwal 121105, Haryana, India (d) Department of Physics, Indian Institute of Technology, New Delhi 110016, India Article History: Received 2 January 2010; Revised 21 May 2010; Accepted 7 June 2010 Article Note: (miscellaneous) Communicated by: Associate Editor Takhir Razykov

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ajhg.2009.01.013 Byline: Lucy Huang (1)(2), Yun Li (1), Andrew B. Singleton (3), John A. Hardy (4), Goncalo Abecasis (1), Noah A. Rosenberg (1)(2)(5), Paul Scheet (1)(6) Abstract: A current approach to mapping complex-disease-susceptibility loci in genome-wide association (GWA) studies involves leveraging the information in a reference database of dense genotype data. By modeling the patterns of linkage disequilibrium in a reference panel, genotypes not directly measured in the study samples can be imputed and tested for disease association. This imputation strategy has been successful for GWA studies in populations well represented by existing reference panels. We used genotypes at 513,008 autosomal single-nucleotide polymorphism (SNP) loci in 443 unrelated individuals from 29 worldwide populations to evaluate the 'portability' of the HapMap reference panels for imputation in studies of diverse populations. When a single HapMap panel was leveraged for imputation of randomly masked genotypes, European populations had the highest imputation accuracy, followed by populations from East Asia, Central and South Asia, the Americas, Oceania, the Middle East, and Africa. For each population, we identified 'optimal' mixtures of reference panels that maximized imputation accuracy, and we found that in most populations, mixtures including individuals from at least two HapMap panels produced the highest imputation accuracy. From a separate survey of additional SNPs typed in the same samples, we evaluated imputation accuracy in the scenario in which all genotypes at a given SNP position were unobserved and were imputed on the basis of data from a commercial 'SNP chip,' again finding that most populations benefited from the use of combinations of two or more HapMap reference panels. Our results can serve as a guide for selecting appropriate reference panels for imputation-based GWA analysis in diverse populations. Author Affiliation: (1) Department of Biostatistics, University of Michigan, Ann Arbor, MI 48109, USA (2) Center for Computational Medicine and Biology, University of Michigan, Ann Arbor, MI 48109, USA (3) Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892, USA (4) Department of Molecular Neuroscience and Reta Lila Weston Institute of Neurological Studies, Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK (5) Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA (6) Department of Epidemiology, University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA Article History: Received 11 September 2008; Revised 9 January 2009; Accepted 16 January 2009 Article Note: (miscellaneous) Published online: February 12, 2009

Electron-induced electron yields of high-resistivity high-yield materials--ceramic polycrystalline aluminum oxide and polymer polyimide (Kapton HN)--were made by using a low-fluence pulsed incident electron beam and charge neutralization electron source to minimize charge accumulation. Large changes in the energy-dependent total yield curves and yield decay curves were observed, even for incident electron fluences of < 3 fC/[mm.sup.2]. The evolution of the electron yield as charge accumulates in the material is modeled in terms of electron recapture based on an extended Chung--Everhart model of the electron emission spectrum. This model is used to explain the anomalies measured in highly insulating high-yield materials and to provide a method for determining the limiting yield spectra of uncharged dielectrics. The relevance of these results to spacecraft charging is also discussed. Index Terms--Charging, dielectrics, electron, emission.

Abstract: Through out this paper an experimental study was carried out to study the static torsion capability of hybrid aluminum glass fiber composite shaft. A hybrid shaft was fabricated using [...]

We investigated the influences of humic acid on the removal of Al tridecamer ([Al.sub.13]) from a bydroxyahiminum (HyA) solution at various humic acid/Al ratios. The Al species contained in the solution were analyzed by using a liquid-state [sup.27]Al-NMR and an atomic absorption spectrometer and fractionated into three Al species: (i) [Al.sub.13], (ii) Al monomer and dimer ([Al.sub.SYM]), and (iii) other undefined species including aggregated/precipitated Al ([Al.sub.NON]). By the addition of humic acid to the HyA solution, the concentration of [Al.sub.13] was rapidly decreased within 0.007 d (10 min). The decrease in [Al.sub.13] and the increase in [Al.sub.NON] were more pronounced at a higher humic acid/Al ratio. When the molar ratio of humic acid carboxylic groups to Al exceeded 0.8, [Al.sub.13] was undetected from solution within 0.007 d. The formation of [Al.sub.13]-humic acid complexes and the aggregation/precipitation of those complexes were a predominant mechanism in removing aqueous [Al.sub.13] at the early stage of the reaction. Approximately 10 mol of carboxylic groups in humic acid were required to remove 1 moi of [Al.sub.13] from the HyA solution. Aqueous [Al.sub.13] had greater preference in precipitating with humic acid than [Al.sub.SYM]. After 5 to 570 d of aging, the concentration of [Al.sub.13] and [Al.sub.NON] also decreased and increased, respectively, both in the presence and absence of humic acid. In conclusion, aqueous [Al.sub.13] would not exist in soil solution under a high humic acid condition.

Synthesis of a series of aluminum complexes containing ketiminate ligands is discussed. Results reveal that the complexes are active towrd the ring-opening polymerization of epsilon-caprolactone. Furthermore, a higher molecular weight polymer results from the aluminum alkyl complexes, whereas the aluminum halide complex forms a lower molecular weight oligomer.

The new fluoroaluminophosphate chain compound is synthesized from isopropylamine units in the presence of hydrogen fluoride. The compound is a one-dimensional aluminophosphate chain exhibiting an Al/P ratio of 1/1.