Efficiency limits for space multi-junction concentrator solar cells

Efficiency limits of single-junction and multi-junction concentrator solar cells are established from the thermodynamic principle of detailed balance. The maximum efficiency limit of single-junction solar cells is35% at500 suns, while that of2-junction solar cells which meet the current matching condition is46%. At the same condition, the maximum efficiency limit of3-junction solar cells with GaAs as middle subcell is52%.?2011 IEEE

Cloning and expression of a novel human galectin cDNA, predominantly expressed in placenta

A novel human galectin cDNA (PPL13) was isolated by screening a human 18-week fetal brain library. The mRNA was predominantly expressed in placenta, while the expression of it was not or barely detectable in he-art, brain, lung, liver, skeletal muscle, kidney, and pancreas by Northern blot. COS-7 cells transfected with cDNA encoding human PPL13 sequestered the protein in nuclei although it lacked any known nuclear localization signal. STS of Unigene Hs. 24236 placed the cDNA to human chromosome 19q13.2. (C) 2001 Elsevier Science B.V. All rights reserved

Flotation separation of wolframite from calcite using a new trisiloxane surfactant as collector

Since wolframite is usually associated with calcite, the separation and enrichment of wolframite by froth flotation remains a great challenge. Herein, a novel trisiloxane surfactant N-(2-aminoethyl)-3-aminopropyltrisiloxane (AATS) was successful synthesized, which was used for the separation of wolframite from calcite for the first time. The flotation separation performance of AATS was studied by flotation test, and its adsorption mechanism was explored based on contact angle, infrared spectrum analysis (FTIR), zeta potential and density functional theory (DFT) calculation. The results of micro-flotation test and binary mixed ore flotation test pointed that AATS had excellent selectivity and more prominent collection capacity for the flotation of wolframite when compared with industrial reagent sodium oleate (NaOL). The measurement results of contact angle proved that AATS improved the hydrophobicity of the wolframite surface. The highly selective adsorption mechanism of AATS surfactant on mineral surfaces were further researched and analyzed by FTIR and zeta potential. The results revealed that AATS surfactant had significant adsorption effect on wolframite, yet almost no adsorption on calcite. DFT calculation indicated that AATS produced electrostatic adsorption with wolframite surface through —N+H3 group