Mineral element content in Ulva lactuca L. with reference to eutrophication in Hong Kong coastal waters

The amounts of tissue nitrogen, phosphorus, potassium, sodium, calcium and iron were estimated in the green alga Ulva lactuca L. collected from 9 rural and 14 urban littoral sites in the waters around Hong Kong Island during 1978 and 1979. The mean levels of tissue nitrogen and phosphorus were respectively 65% and 87% more in urban sites than in rural ones. Very significant correlation (r = 0.920) was found between the logarithmic concentration of seawater inorganic nitrogen and that of tissue nitrogen. The same applied to soluble reactive phosphorus in seawater and tissue phosphorus (r = 0.886). The levels of potassium, sodium and calcium in the alga were relatively uniform. However considerable variation in the level of iron was detected. The potential use of Ulva as an indicator species for eutrophication is discussed.     

香港茜草科植物新记录

查阅馆藏植物标本,有3种茜草科植物：丹草（Hedyotis herbacea）、小耳草（H.pumila）和蕴璋耳草（Scleromitrion koanum）为香港新记录。这些资料为香港的生物多样性工作提供了基础数据。     

Nanomoulding of Functional Materials,a Versatile Complementary Pattern Replication Method to Nanoimprinting

We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding combined with layer transfer enables the replication of arbitrary surface patterns from a master structure onto the functional material. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes. In particular we demonstrate the fabrication of patterned transparent zinc oxide electrodes for light trapping applications in solar cells.     

A Comparison of Ship-Recycling Legislation Between Chinese Law and the 2009 Hong Kong Convention

This article discusses the Chinese legal framework in relation to ship recycling and suggests that the various legislation, standards, and opinions provide disorderly and nosystematic regulation. A uniform law specifically regulating the ship-recycling industry should be adopted by China, with a single competent authority empowered to supervise ship-recycling activities, that will effectively implement the 2009 Hong Kong International Convention for the Safe and Environmentally Sound Recycling of Ships.     

Highly Stable Transparent Conductive Silver Grid/PEDOT:PSS Electrodes for Integrated Bifunctional Flexible Electrochromic Supercapacitors

Silver grids are attractive for replacing indium tin oxide as flexible transparent conductors. This work aims to improve the electrochemical stability of silver‐based transparent conductors. A silver grid/PEDOT:PSS hybrid film with high conductivity and excellent stability is successfully fabricated. Its functionality for flexible electrochromic applications is demonstrated by coating one layer of WO₃ nanoparticles on the silver grid/PEDOT:PSS hybrid film. This hybrid structure presents a large optical modulation of 81.9% at 633 nm, fast switching, and high coloration efficiency (124.5 cm² C^?1). More importantly, an excellent electrochemical cycling stability (sustaining 79.1% of their initial transmittance modulation after 1000 cycles) and remarkable mechanical flexibility (optical modulation decay of only 7.5% after 1200 compressive bending cycles) is achieved. A novel smart supercapacitor is presented that functions as a regular energy‐storage device and simultaneously monitors the level of stored energy by a rapid and reversible color variation even at high current charge/discharge conditions. The film sustains an optical modulation of 87.7% and a specific capacitance of 67.2% at 10 A g^?1 compared to their initial value at a current density of 1 A g^?1. The high‐performance silver grid/PEDOT:PSS hybrid transparent films exhibit promising features for various emerging flexible electronics and optoelectronic devices.     

Efficient,Large Area,and Thick Junction Polymer Solar Cells with Balanced Mobilities and Low Defect Densities

The high power conversion efficiencies (PCEs) of laboratory‐scale polymer‐based organic solar cells are yet to translate to large area modules because of a number of factors including the relatively large sheet resistance of available transparent conducting electrodes (TCEs), and the high defect densities associated with thin organic semiconductor junctions. The TCE problem limits device architectures to narrow connected strips (<1 cm) causing serious fabrication difficulties and extra costs. Thin junctions are required because of poor charge transport (imbalanced mobilities) in the constituent organic semiconductors. These issues are addressed using a combination of approaches to create thick junctions conformally coated on low sheet resistance metal grid TCEs. An essential feature of these thick junctions is balanced carrier mobilities, which affords high fill factors and efficient carrier extraction. Conformal coating is achieved by promoting enhanced intermolecular interactions in the coating solution using a high molecular weight polymeric semiconductor and appropriate solvent system. This combination of balanced mobilities, conformal coating and metallic grid TCEs is a simple and generic approach to the fabrication of defect‐free large area organic solar cells (OSCs). The approach is demonstrated with 25 cm² monolithic devices possessing aperture‐corrected power conversion efficiencies of 5% and fill factors exceeding 0.5.