Harmonised life-cycle indicators of nuclear-based hydrogen

When comparing the life-cycle environmental performance of hydrogen energy systems, significant concerns arise due to potential methodological inconsistencies between case studies. In this regard, protocols for harmonised life cycle assessment (LCA) of hydrogen energy systems are currently available to mitigate these concerns. These protocols have already been applied to conventional hydrogen from steam methane reforming as well as to a large number of both fossil and renewable hydrogen options, allowing robust comparisons between them. However, harmonised life-cycle indicators of nuclear-based hydrogen options are not yet available in the literature. This study fills this gap by using the recently developed software GreenH₂armony® to calculate the harmonised carbon, energy and acidification footprints of nuclear-based hydrogen produced through different pathways (viz., low-temperature electrolysis, high-temperature electrolysis, and thermochemical cycles). Overall, the harmonised case studies of nuclear-based hydrogen show a generally good performance in terms of carbon footprint and acidification, but an unfavourable performance in terms of non-renewable energy footprint.     

Sulphonated (PVDF-co-HFP)-graphene oxide composite polymer electrolyte membrane for HI decomposition by electrolysis in thermochemical iodine-sulphur cycle for hydrogen production

In overall iodine-sulphur (I-S) cycle (Bunsen reaction), HI decomposition is a serious challenge for improvement in H₂ production efficiency. Herein, we are reporting an electrochemical process for HI decomposition and simultaneous H₂ and I₂ production. Commercial Nafion 117 membrane has been generally utilized as a separator, which also showed huge water transport (electro-osmosis), and deterioration in conductivity due to dehydration. We report sulphonated poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) (SCP) and sulphonated graphene oxide (SGO) composite stable and efficient polymer electrolyte membrane (PEM) for HI electrolysis and H₂ production. Different SCP/SGO composite PEMs were prepared and extensively characterized for water content, ion-exchange capacity (IEC), conductivity, and stabilities (mechanical, chemical, and thermal) in comparison with commercial Nafion117 membrane. Most suitable optimized SCP/SGO-30 composite PEM exhibited 6.78 × 10^?2 S cm^?1 conductivity in comparison with 9.60 × 10^?2 S cm^?1 for Nafion® 117. The electro-osmotic flux ofSCP/SGO-30 composite PEM (2.53 × 10^?4 cm s^?1) was also comparatively lower than Nafion® 117 membrane (2.75 × 10^?4 cm s^?1). For HI electrolysis experiments, SCP/SGO-30 composite PEM showed good performance such as 93.4% current efficiency (η), and 0.043 kWh/mol-H₂ power consumption (Ψ). Further, intelligent architecture of SCP/SGO composite PEM, in which hydrophilic SGO was introduced between fluorinated polymer by strong hydrogen bonding, high efficiency and performance make them suitable candidate for electrochemical HI decomposition, and other diversified electrochemical processes.     

Geothermal and solar energy–based multigeneration system for a district

In this study, parabolic trough collector with an integrated source of geothermal water is used with regenerative Rankine cycle with an open feedwater heater, an electrolyzer, and an absorption cooling system. The absorption fluids used in the solar collectors were Al₂O₃‐ and Fe₂O₃‐based nanofluids. Detailed energetic and exergetic analyses are done for the whole system including all the components. A comparative analysis of both the used working fluids is done and plotted against their different results. The parameters that are varied to change the output of the system are ambient temperature, solar irradiance, the percentage of nanofluids, the mass flow rate of the geothermal well, the temperature gradient of the geothermal well that had an effect on the net power produced, and the outlet temperature of the solar collector overall energetic and exergetic efficiencies. Other useful outputs by this domestic integrated multigeneration system are the heating of domestic water, space heating (maintaining the temperature at 40°C‐50°C), and desalination of seawater (flash distillation). The hydrogen production rate for both the fluids diverges with each other, both producing average from 0.00490 to 0.0567 g/s.     

Challenges in forming inferences from limited data: a case study of malaria parasite maturation

Inferring biological processes from population dynamics is a common challenge in ecology, particularly when faced with incomplete data. This challenge extends to inferring parasite traits from within-host infection dynamics. We focus on rodent malaria infections (Plasmodium berghei), a system for which previous work inferred an immune-mediated extension in the length of the parasite development cycle within red blood cells. By developing a system of delay-differential equations to describe within-host infection dynamics and simulating data, we demonstrate the potential to obtain biased estimates of parasite (and host) traits when key biological processes are not considered. Despite generating infection dynamics using a fixed parasite developmental cycle length, we find that known sources of measurement bias in parasite stage and abundance data can affect estimates of parasite developmental duration, with stage misclassification driving inferences about extended cycle length. We discuss alternative protocols and statistical methods that can mitigate such misestimation.     

A Phenylacetamide Resveratrol Derivative Exerts Inhibitory Effects on Breast Cancer Cell Growth

Resveratrol (RSV) is a natural compound that displays several pharmacological properties, including anti-cancer actions. However, its clinical application is limited because of its low solubility and bioavailability. Here, the antiproliferative and anti-inflammatory activity of a series of phenylacetamide RSV derivatives has been evaluated in several cancer cell lines. These derivatives contain a monosubstituted aromatic ring that could mimic the RSV phenolic nucleus and a longer flexible chain that could confer a better stability and bioavailability than RSV. Using MTT assay, we demonstrated that most derivatives exerted antiproliferative effects in almost all of the cancer cell lines tested. Among them, derivative 2, that showed greater bioavailability than RSV, was the most active, particularly against estrogen receptor positive (ER+) MCF7 and estrogen receptor negative (ER-) MDA-MB231 breast cancer cell lines. Moreover, we demonstrated that these derivatives, particularly derivative 2, were able to inhibit NO and ROS synthesis and PGE2 secretion in lipopolysaccharide (LPS)-activated U937 human monocytic cells (derived from a histiocytoma). In order to define the molecular mechanisms underlying the antiproliferative effects of derivative 2, we found that it determined cell cycle arrest at the G1 phase, modified the expression of cell cycle regulatory proteins, and ultimately triggered apoptotic cell death in both breast cancer cell lines. Taken together, these results highlight the studied RSV derivatives, particularly derivative 2, as promising tools for the development of new and more bioavailable derivatives useful in the treatment of breast cancer.     

城市水循环演变及对策分析

全球气候变化和快速城市化改变了自然水循环过程,使水循环呈现"自然-社会"二元特征。城市是二元水循环耦合程度最深的区域,城市水循环的驱动力、结构与过程呈现复杂化,由此引发的城市水问题越来越突出,未来城市水循环面临严峻挑战。本文在识别城市水循环的演变历程和机理的基础上,解析了城市水问题的产生根源。以城市水问题以及未来城市水循环发展趋势为导向,提出了未来城市水循环调控的总体思路,论述了未来城市水循环调控的"理水""用水""治水""管水"四大战略,阐明了以"安""和""畅""保""节""回""净""智"八字方针为指导的未来城市水循环调控实现途径。     

Influences of chitosan on freeze–thaw stability of Arenga pinnata starch

This study aims to investigate chitosan (CS) with five different molecular weight (Mw) on freeze–thaw stability of Arenga pinnata starch (APS) gel subjected to five freeze–thaw cycles (FTC). The syneresis of APS gels was reduced by adding CS and the APS gel with high Mw CS had lower syneresis duo to a higher water holding capacity (P < 0.05). The addition of CS significantly decreased the hardness and molecular ordered structure of APS gel. In addition, CS could improve the microstructural stability. The results suggested that CS could effectively improve the freeze–thaw stability of APS gel, and CS with higher Mw might have more practical utility to improve stability of APS gel.     

Fabrication,permeation, and corrosion stability measurements of silica membranes for HI decomposition in the thermochemical iodine–sulfur process

In this study, a corrosion-stable silica membrane was developed to be used in H₂ purification during the hydrogen iodide decomposition (2HI → H₂ + I₂), which is a new application of the silica membranes. From a practical perspective, the membrane separation length was enlarged up to 400 mm and one end of the membrane tubes was closed to avoid any thermal variation along the membrane length and sealing issues. The silica membranes consisted of a three-layer structure comprising a porous α-Al₂O₃ ceramic support, an intermediate layer, and a top silica layer. The intermediate layer was composed of γ-Al₂O₃ or silica, and the top silica layer that is H₂ selective was prepared via counter-diffusion chemical vapor deposition of a hexyltrimethoxysilane.To the best of our knowledge, this is the first report of 400-mm-long closed-end silica membranes supported on Si-formed α-Al₂O₃ tubes produced via chemical vapor deposition method. A 400-mm-long closed-end membrane using a Si-formed α-Al₂O₃ tube exhibited a higher H₂/SF₆ selectivity of 1240 but lower H₂ permeance of 1.4 × 10⁻⁷ mol Pa⁻¹ m⁻² s⁻¹ with compared with the membrane using a γ-Al₂O₃-formed α-Al₂O₃ tube (907 and 5.6 × 10⁻⁷ mol Pa⁻¹ m⁻² s⁻¹, respectively). The membrane using the Si-formed α-Al₂O₃ tube was more stable in corrosive HI gas than a membrane with a γ-Al₂O₃-formed α-Al₂O₃ tube after 300 h of stability tests. In conclusion, the developed silica membranes using the Si-formed α-Al₂O₃ tubes seem suitable for membrane reactors that produce H₂ on large scale using HI decomposition in the thermochemical iodine–sulfur process.     

Environmental and energy life cycle analyses of passenger vehicle systems using fossil fuel-derived hydrogen

Hydrogen energy utilization is expected due to its environmental and energy efficiencies. However, many issues remain to be solved in the social implementation of hydrogen energy through water electrolysis. This analyzes and compares the energy consumption and GHG emissions of fossil fuel-derived hydrogen and gasoline energy systems over their entire life cycle. The results demonstrate that for similar vehicle weights, the hydrogen energy system consumes 1.8 MJ/km less energy and emits 0.15 kg-CO 2 eq./km fewer GHG emissions than those of the gasoline energy system. Hydrogen derived from fossil fuels may contribute to future energy systems due to its stable energy supply and economic efficiency. Lowering the power source carbon content also improved the environmental and energy efficiencies of hydrogen energy derived from fossil fuels.     

Life Cycle Assessment of Substitute Natural Gas production from biomass and electrolytic hydrogen

The synthesis of a Substitute Natural Gas (SNG) that is compatible with the gas grid composition requirements by using surplus electricity from renewable energy sources looks a favourable solution to store large quantities of electricity and to decarbonise the gas grid network while maintaining the same infrastructure. The most promising layouts for SNG production and the conditions under which SNG synthesis reduces the environmental impacts if compared to its fossil alternative is still largely untapped. In this work, six different layouts for the production of SNG and electricity from biomass and fluctuating electricity are compared from the environmental point of view by means of Life Cycle Assessment (LCA) methodology. Global Warming Potential (GWP), Cumulative Energy Demand (CED) and Acidification Potential (AP) are selected as impact indicators for this analysis. The influence of key LCA methodological aspects on the conclusions is also explored. In particular, two different functional units are chosen: 1 kg of SNG produced and 1 MJ of output energy (SNG and electricity). Furthermore, different approaches dealing with co-production of electricity are also applied. The results show that the layout based on hydrogasification has the lowest impacts on all the considered cases apart from the GWP and the CED with SNG mass as the functional unit and the avoided burden approach. Finally, the selection of the multifunctionality approach is found to have a significant influence on technology ranking.