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A disturbance of reactive oxygen species (ROS) homeostasis may cause the pathogenesis of many diseases. Inspired by natural photosynthesis, this work proposes a photo-driven H2-evolving liposomal nanoplatform (Lip NP) that comprises an upconversion nanoparticle (UCNP) that is conjugated with gold nanoparticles (AuNPs) via a ROS-responsive linker, which is encapsulated inside the liposomal system in which the lipid bilayer embeds chlorophyll a (Chla). The UCNP functions as a transducer, converting NIR light into upconversion luminescence for simultaneous imaging and therapy in situ. Functioning as light-harvesting antennas, AuNPs are used to detect the local concentration of ROS for FRET biosensing, while the Chla activates the photosynthesis of H2 gas to scavenge local excess ROS. The results thus obtained indicate the potential of using the Lip NPs in the analysis of biological tissues, restoring their ROS homeostasis, possibly preventing the initiation and progression of diseases. Hydrogen can be used to reduce the concentration of reactive oxygen species (ROS), but its delivery to diseased tissues is challenging due to its low solubility. Here the authors develop a photosynthesis-inspired FRET nanocomplex to detect and scavenge local excess of ROS in the tissue using photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

SUMMARY In order to evaluate quantitatively the effect of syngas cooling modes of slurry feed gasification on the hydrogen production process, two processes of gasification for hydrogen with petcoke as the feedstock were developed in the paper, which were petcoke water slurry + total quench + high water/dry gas (W/G) and petcoke water slurry + radiant syngas cooler + quench + low W/G, named by cases 1 and 2, respectively. The two processes were simulated by using Aspen Plus. The results show that with the operating parameters used by the system, the energy conversion efficiency of cases 1 and 2 are the same, which is 74%. The exergy efficiency of case 2 is higher than that of case 1, which are 62% and 61%, respectively. The water consumption of cases 1 and 2 are almost the same. However, the proportion of high-quality steam produced in case 2 is higher, and the quantity of high-quality steam is larger than that of case 1. The system profit of case 2 is better than that of case 1. Thus, case 2 is better than case 1 and is more suitable for petcoke gasification for hydrogen taking the gasification performance, energy utilization analysis, system water utility analysis, and system performance yield rate into account. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: A full factorial design was conducted to investigate the combined effects of temperatures and initial pH on fermentative hydrogen production by mixed cultures in batch tests. The experimental results showed that the modified Logistic model can be used to describe the progress of cumulative hydrogen production in the batch tests of this study. The modified Ratkowsky model can be used to describe the combined effects of the temperatures and initial pH on the substrate degradation efficiency, hydrogen yield and average hydrogen production rate. The temperatures and initial pH had interactive impact on fermentative hydrogen production. The maximum substrate degradation efficiency, the maximum hydrogen yield and the maximum average hydrogen production rate was predicted at the temperature of 37.8°C and the initial pH of 7.1, 37.4°C and 6.9, and 38.2°C and 7.2, respectively. In general, the optimal temperature for the fermentative hydrogen production was around 37.8°C and the optimal initial pH for the fermentative hydrogen production was around 7.1. [Copyright &y& Elsevier]