Developing high-efficiency and low-cost photocatalysts by avoiding expensive noble metals, yet remarkably improving H2 evolution performance, is a great challenge. Noble-metal-free catalysts ...containing Co(Fe)NC moieties have been widely reported in recent years for electrochemical oxygen reduction reaction and have also gained noticeable interest for organic transformation. However, to date, no prior studies are available in the literature about the activity of N-coordinated metal centers for photocatalytic H2 evolution. Herein, a new photocatalyst containing g-C3N4 decorated with CoP nanodots constructed from low-cost precursors is reported. It is for the first time revealed that the unique P(delta-)Co(delta+)N(delta-) surface bonding states lead to much superior H2 evolution activity (96.2 µmol h-1) compared to noble metal (Pt)-decorated g-C3N4 photocatalyst (32.3 µmol h-1). The quantum efficiency of 12.4% at 420 nm is also much higher than the record values (asymp2%) of other transition metal cocatalysts-loaded g-C3N4. It is believed that this work marks an important step toward developing high-performance and low-cost photocatalytic materials for H2 evolution.
The Illumina DNA sequencing platform generates accurate but short reads, which can be used to produce accurate but fragmented genome assemblies. Pacific Biosciences and Oxford Nanopore Technologies ...DNA sequencing platforms generate long reads that can produce complete genome assemblies, but the sequencing is more expensive and error-prone. There is significant interest in combining data from these complementary sequencing technologies to generate more accurate "hybrid" assemblies. However, few tools exist that truly leverage the benefits of both types of data, namely the accuracy of short reads and the structural resolving power of long reads. Here we present Unicycler, a new tool for assembling bacterial genomes from a combination of short and long reads, which produces assemblies that are accurate, complete and cost-effective. Unicycler builds an initial assembly graph from short reads using the de novo assembler SPAdes and then simplifies the graph using information from short and long reads. Unicycler uses a novel semi-global aligner to align long reads to the assembly graph. Tests on both synthetic and real reads show Unicycler can assemble larger contigs with fewer misassemblies than other hybrid assemblers, even when long-read depth and accuracy are low. Unicycler is open source (GPLv3) and available at github.com/rrwick/Unicycler.
We compare carbon (and hence energy) costs of the different modes of phosphorus (P) acquisition by vascular land plants. Phosphorus-acquisition modes are considered to be mechanisms of plants ...together with their root symbionts and structures such as cluster roots involved in mobilising or absorbing P. Phosphorus sources considered are soluble and insoluble inorganic and organic pools. Costs include operating the P-acquisition mechanisms, and resource requirements to construct and maintain them. For most modes, costs increase as the relevant soil P concentration declines. Costs can thus be divided into a component incurred irrespective of soil Pconcentration, and a component describinghowquickly costs increase as the soil P concentration declines. Differences in sensitivity of costs to soil P concentration arise mainly from how economically mycorrhizal fungal hyphae or roots that explore the soil volume are constructed, and from costs of exudates that hydrolyse or mobilise insoluble P forms. In general, modes of acquisition requiring least carbon at high soil P concentrations experience a steeper increase in costs as soil P concentrations decline. The relationships between costs and concentrations suggest some reasons why different modes coexist, and why the mixture of acquisition modes differs between sites.
Atmospheric nitrogen (N) deposition has substantial effects on forest ecosystems. The effects of N deposition on understorey plants have been simulated by spraying N on the forest floor. Such ...understorey addition of N (UAN) might simulate atmospheric N deposition in a biased manner, because it bypasses the canopy.
We compared the effects of UAN and canopy addition of N (CAN) at 0, 25 and 50 kg N ha−1 year–1 on SLA, leaf construction costs (CC), concentrations of leaf carbon (C), nitrogen (N), phosphorus (P), minerals (Mineral), nitrate (NO3‐), lignin (Lignin), lipids (Lipid), organic acids (OA), soluble phenolics (SP), total non‐structural carbohydrates (TNC) and total structural carbohydrates (TSC) in six dominant understorey species in a subtropical evergreen forest after 5 years of N treatments.
We found that leaf CC, C, Lignin, OA, TNC and TSC were significantly affected by N addition approach and rate, but leaf P and Lipid were affected by N addition approach and N addition rate respectively; leaf CC, C, P, OA and TNC were significantly lower under UAN than under CAN, but leaf TSC and Lignin were significantly higher and lower, respectively, under UAN than under CAN at 50 kg N ha−1 year–1; the decline of leaf C and Lignin contributed to the significantly lower leaf CC under UAN than under CAN.
Synthesis. We show that canopy and understorey N addition exerted significantly different effects on leaf traits of understorey plants. The results indicate that understorey plants in subtropical forest respond differently to UAN from those to atmospheric deposition of N. Further studies are warranted to evaluate the unbiased ecological processes and functions of forest ecosystem responding to atmospheric N deposition via both CAN and UAN experiments over a longer term.
Nitrogen addition approach and rate had negative effects on leaf construction costs (CC) directly and indirectly via influencing leaf traits of understorey plants, indicating canopy and understorey nitrogen addition exerted significantly different effects on understorey plants. The results suggest that understorey plants in subtropical forest respond differently to understorey addition of nitrogen from those to atmospheric deposition of N.
The field of RNA nanotechnology has advanced rapidly during the past decade. A variety of programmable RNA nanoparticles with defined shape, size, and stoichiometry have been developed for diverse ...applications in nanobiotechnology. The rising popularity of RNA nanoparticles is due to a number of factors: (1) removing the concern of RNA degradation in vitro and in vivo by introducing chemical modification into nucleotides without significant alteration of the RNA property in folding and self-assembly; (2) confirming the concept that RNA displays very high thermodynamic stability and is suitable for in vivo trafficking and other applications; (3) obtaining the knowledge to tune the immunogenic properties of synthetic RNA constructs for in vivo applications; (4) increased understanding of the 4D structure and intermolecular interaction of RNA molecules; (5) developing methods to control shape, size, and stoichiometry of RNA nanoparticles; (6) increasing knowledge of regulation and processing functions of RNA in cells; (7) decreasing cost of RNA production by biological and chemical synthesis; and (8) proving the concept that RNA is a safe and specific therapeutic modality for cancer and other diseases with little or no accumulation in vital organs. Other applications of RNA nanotechnology, such as adapting them to construct 2D, 3D, and 4D structures for use in tissue engineering, biosensing, resistive biomemory, and potential computer logic gate modules, have stimulated the interest of the scientific community. This review aims to outline the current state of the art of RNA nanoparticles as programmable smart complexes and offers perspectives on the promising avenues of research in this fast-growing field.
Although automation has been actively and successfully used in different industries since the 1970s, its application to the construction industry is still rare or not fully exploited. In order to ...help provide the construction industry with an additional incentive to adopt more automation, an investigation was undertaken to assess the effects of digital fabrication (dfab) on productivity by analyzing the cost and time required for the construction of a robotically-fabricated complex concrete wall onsite. After defining the different tasks for the conventional and robotically fabricated concrete wall, data was collected from different sources and used in a simulation to describe the distribution of time and cost for the different construction scenarios. In the example, it was found that productivity is higher when the robotic construction method is used for complex walls, indicating that it is possible to obtain significant economic benefit from the use of additive dfab to construct complex structures. Further research is required to assess the social impacts of using dfab.
•Digital fabrication (dfab) has great potential to advance the construction industry.•Productivity is higher when dfab is used for complex structures.•No additional cost from robotic fabrication if the complexity of the wall increases•Dfab will transform current roles in the planning and execution of projects.•Further research is required to assess the social impacts of dfab.
Droit international MASOUMI, Khazar
Revue juridique de l'environnement,
01/2017, Volume:
42, Issue:
2
Journal Article
Peer reviewed
- Affaire relative à certaines activités menées par le Nicaragua dans la région frontalière (Costa Rica c. Nicaragua) - Affaire relative à la construction d’une route au Costa Rica le long du fleuve ...San Juan (Nicaragua c. Costa Rica) - Obligation de réaliser une évaluation de l’impact sur l’environnement - Obligation de notification et de constatation et obligation de ne pas causer de dommage au territoire d’un autre État
With more electric buses, the optimal location of charging station plays an important role for bus electrification. This paper proposes a location planning model of electric bus fast-charging ...stations for the electric bus transit system, that takes the bus operation network and the distribution network into account. The model 1) simulates the operation network of electric buses thoroughly to obtain the charging demand of electric buses and 2) takes into account of the absorption capacity of distribution network and other constraints in the siting and capacity determination stage. The objective of the model is to minimize the sum of the construction cost, operation and maintenance costs, travel cost to charging stations, and the cost of power loss for charging stations at established bus terminus. The Affinity Propagation method is adopted to cluster the bus terminuses in order to obtain a preliminary number of charging stations. Subsequently, the Binary Particle Swarm Optimization algorithm is used to optimize the site selection and capacity. Finally, the model is applied to simulate and analyze the bus operation network of a coastal city in South China. The case study shows that the model can effectively optimize the layout of bus charging stations for the city.
•Proposed a charging demand model for electric buses with bus operation schedule.•Bus terminuses clustering with Affinity Propagation (AP) reduces charging stations.•Binary Particle Swarm Optimization (BPSO) for discrete charging site selection.•Examined various departure intervals, on-board battery quantity, and charger power.•Proposed AP-BPSO identifies the lowest investment cost and reduces modelling time.
Manage water in a green way Palmer, Margaret A.; Liu, Junguo; Matthews, John H. ...
Science (American Association for the Advancement of Science),
08/2015, Volume:
349, Issue:
6248
Journal Article
Peer reviewed
Open access
Reliance on “hard,” human-engineered structures—“gray” infrastructure—has been the conventional way to manage water needs for economic development. But building dams, piping water, and constructing ...protective barriers is capital intensive and may address only a few water problems (
1
). Gray infrastructure often damages or eliminates biophysical processes necessary to sustain people, ecosystems and habitats, and livelihoods. Consequently, there is renewed focus on “green” infrastructure, which can be more flexible and cost effective for providing benefits besides water provision. Supplementing or integrating gray infrastructure with biophysical systems is critical to meeting current and future water needs. Gray and green infrastructures combined are synergistic and can have superior results to one or the other.
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