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Seaweed fibre is usually discarded as biomass waste after extraction of useful ingredients from seaweed. However this seaweed fibre, a natural abundant cellulose material with uniform dimensions 10 times smaller than other plant-based fibre can be utilized as electrode material for energy storage. In this work, we converted seaweed fibre into conductive carbon electrodes by a thermal carbonisation method. The morphology, chemical composition and conductivity are highly influenced by the carbonisation temperature. In comparison to other biomass sources such as cotton pulp, seaweed fibre is finer, smoother and more conductive at low carbonisation temperature. These carbonized seaweeds were then used as a supercapacitor, giving a high supercapacitance (226.3 Fg−1) at the carbonisation temperature of 900°C, and good stability within 2400 cycles. This specific capacitance is significantly higher than values obtained from filter paper or cotton pulp.

Abstract Eumelanin, a type of skin melanin pigment, possesses the ability to absorb a wide range of wavelengths, providing protection to the skin from ultraviolet radiation. However, excessive production of eumelanin may result in hyperpigmentation. Consequently, the development of skin-brightening products that suppress eumelanin synthesis to achieve a lighter and more even skin tone is necessary. The present study investigated the potential application of Melaleuca leucadendron as a natural skin-brightening agent. We investigated the effects of the ethanol leaf extract of M. leucadendron on α-melanocyte-stimulating hormone-induced melanogenesis in B16F10 cells and identified the key factors involved in melanogenesis. This leaf extract significantly inhibited melanin production by downregulating the expression of microphthalmia-associated transcription factor, tyrosinase, tyrosinase-related protein 1, and dopachrome tautomerase without causing cytotoxicity. Furthermore, it substantially reduced melanin content in a 3D skin model. These results suggest that the extract of M. leucadendron is a promising, safe, and effective skin-brightening agent.

The demand for energy sources with high energy densities continues to push the limits of Ni-rich layered oxides, which are currently the most promising cathode materials in automobile batteries. Although most current research is focused on extending battery life using Ni-rich layered cathodes, long-term cycling stability using a full cell is yet to be demonstrated. Here, we introduce Li[Ni0.90Co0.09Ta0.01]O2, which exhibits 90% capacity retention after 2,000 cycles at full depth of discharge (DOD) and a cathode energy density >850 Wh kg−1. In contrast, the currently most sought-after Li[Ni0.90Co0.09Al0.01]O2 cathode loses ~40% of its initial capacity within 500 cycles at full DOD. Cycling stability is achieved by radially aligned primary particles with [003] crystallographic texture that effectively dissipate the internal strain occurring in the deeply charged state, while the substitution of Ni3+ with higher valence ions induces ordered occupation of Ni ions in the Li slab and stabilizes the delithiated structure. Nickel-rich layered oxide cathodes are at the forefront of the development of automobile batteries. The authors report an atomic and microstructural engineering design for a Li[Ni0.90Co0.09Ta0.01]O2 cathode that exhibits outstanding long-term cyclability and high energy at full depth of discharge in full cells.

We investigate the possible causes for inter-model spread in tropical zonal-mean precipitation pattern, which is divided into hemispherically symmetric and anti-symmetric modes via empirical orthogonal function analysis. The symmetric pattern characterizes the leading mode and is tightly related to the seasonal amplitude of maximum precipitation position. The energetic constraints link the symmetric pattern to the seasonal amplitude in cross-equatorial atmospheric energy transport $$ {\text{AET}}_{0} $$ and the annual-mean equatorial net energy input $$ {\text{NEI}}_{0} $$ . Decomposition of $$ {\text{AET}}_{0} $$ into the energetics variables indicates that the inter-model spread in symmetric precipitation pattern is correlated with the inter-model spread in clear-sky atmospheric shortwave absorption, which most likely arises due to differences in radiative transfer parameterizations rather than water vapor patterns. Among the components that consist $$ {\text{NEI}}_{0} $$ , the inter-model spread in symmetric precipitation pattern is mostly associated with the inter-model spread in net surface energy flux in the equatorial region, which is modulated by the strength of cooling by equatorial upwelling. Our results provide clues to understand the mechanism of tropical precipitation bias, thereby providing guidance for model improvements.

The process of urbanization has been shown to be important for economic development, environmental impacts and human wellbeing, particularly in developing countries. In this paper we compare structure, data sources and scenario results of four integrated assessment models that are capable of analyzing different aspects of urbanization. The comparison focuses on residential sector energy use and related CO2 emissions based on a set of urbanization scenarios for China and India. Important insights from this model comparison include that (i) total fossil fuel and industrial CO2 emissions at the regional level are not very sensitive to alternative rates of urbanization and are largely dependent on the linkage between urbanization and economic growth via differentiated labor productivity in urban and rural areas, (ii) alternative urbanization pathways may yield different results for the share of solid fuels in residential energy use, thereby affecting the number of people relying on these fuels and the associated adverse health impacts, and (iii) alternative economic growth scenarios can only be assessed for their welfare implications if urban and rural household are distinguished, even though that distinction does not always strongly affect aggregate outcomes which is often due to two effects that compensate each other in total. It can be concluded that urbanization and heterogeneity of households and consumers are clearly relevant for distributional effects and associated health and social impacts. (C) 2012 Elsevier B.V. All rights reserved.

This work investigates the preparation of a catalytic complex of palladium nanoparticles supported on novel Schiff base modified chitosan-Unye bentonite microcapsules (Pd NPs@CS-UN). The complex has been characterized by FT-IR, EDS, XRD, TEM, HRTEM, Raman, ICP-OES and elemental mapping analyses. Pd NPs@CS-UN was used as a catalyst for Sonogashira coupling reactions between aryl halides and acetylenes, employing K2CO3 as the base and EtOH as a green solvent under aerobic conditions in which it showed high efficacy. Pd NPs@CS-UN was regenerated by filtration after the completion of the reaction. This catalytic process has many advantages including simple methodology, high yields, and easy work-up. The catalytic performance does not notably change even after five consecutive runs.

Abstract Crystal-violet staining, microscopy with image analysis, and quantitative PCR (qPCR) were compared to examine biofilm dynamics. Biofilms of 30 polycultures comprising 15 bacterial species were monitored for 14 days. Collectively, qPCR (representing population) revealed a different growth pattern compared to staining (biomass) and microscopy (colonization): biomass and colonization gradually increased over time, whereas population increased rapidly for the first seven days and leveled off. Temporal forms were categorized into two growth patterns: continuous increase (CI) and non-continuous increase. Staining and microscopy showed similar odds of detecting the CI pattern (27 and 23 polycultures, respectively) across polycultures, greater than that of qPCR (14 polycultures) (P < 0.05). All three methods revealed the identical patterns for 13 polycultures. Staining with microscopy, staining with qPCR, and microscopy with qPCR found the same patterns in 22, 15, and 19 polycultures, respectively. Additionally, staining was quantitatively agreed with microscopy (P < 0.05; R2 > 0.50), whereas neither staining nor microscopy strongly agreed with qPCR (P < 0.05; R2 ≤ 0.22). Collectively, staining was more compatible with microscopy than qPCR in characterizing biofilm dynamics and quantifying biofilms owing to the difference between population growth and biofilm expansion. The concurrent use of qPCR with biomass estimations allows for accurate and comprehensive biofilm quantification.