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Abstract The Mediterranean region is one of the most vulnerable regions to climate change. The majority of climate models forecast a rise in temperatures and less rainfall, which have been observed in recent decades. These changes will affect several vegetation properties, especially phenological dynamics and traits, by increasing drought intensity and recurrence. In this climate change context, the present study aims to assess the evolution of vegetation state and its relation with the climate dynamics in the Mediterranean forest region of northeast Tunisia using Land Surface Phenology (LSP) metrics and the vegetation index (NDVI) analysis from 2000 to 2017. To conduct this work, we used precipitation and temperature data from the two closest weather stations and 16-day NDVI composite images from the MODIS satellite source, with 250-m spatial resolution. Three phenological metrics— start of season (SOS), end of season (EOS), and length of season (LOS) — were obtained and compared for different vegetation types. The LSP variation in response to climatic metrics was also analyzed. The results showed that the LSP in our study area changed significantly during the 2000–2017 period, which includes an average 7.8 days delay in the SOS, an average advance in the EOS by 5 days, and LOS shortened by an average 12.8 days. Autumn (Pr_9) and spring (Pr_3 and P3_4) precipitations, as well as maximum temperature (Tx9+10), represent the best climate parameters to explain the changes in LSP. Both the NDVI and SPEI showed a significant high correlation (p

This report aims to provide concept designs to integrate the SunDial/TES system with the MANDREKAS and ArcelorMittal end-users. These concept designs are important to understand how the ASTEP system will be integrated with the end-users including the tailored designs for the specific needs of each end-user. The end-user specific ASTEP system is introduced and existing heating/cooling systems are explained in schematic diagrams. A small number of integration options are presented in detailed schematics. Possible integration components such as steam generator for MANDREKAS and pipe heater for ArcelorMittal are investigated at the component level. In addition, key fluid properties at the critical locations such as inlet and outlet of the components are summarised.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The use of plastic materials in agriculture causes the serious drawback of huge quantities of waste. The introduction of biodegradable materials, which can be disposed directly into the soil, can be one possible solution to this problem. Biodegradable materials are actually innovative materials; therefore, their physical properties must be evaluated in relation to their functionality during the use in field. In the present research results of experimental tests carried out on biodegradable films used in strawberries protected cultivation are presented. The decay of some relevant physical parameters of biodegradable films during the cultivation period was monitored by laboratory tests (SEM analysis, mechanical tensile tests and infrared reflectance spectroscopy). Infrared spectroscopy clearly indicated that the mechanical degradation starts from the starch component of the material. Tensile tests showed that the value of elongation at break of biodegradable materials decreased in some cases by 300% after 10 days of field application

Climate-controlled changes in eustatic sea level (ESL) are linked to transfers of water between ocean and land, thus offering a rare insight into the past hydrological cycle. In this study, we examine the timing and phase of Milankovitch-scale ESL cycles in the peak Cretaceous greenhouse, the early Turonian (-93-94 million years, Myr, ago). A high-resolution astronomical framework established for the Bohemian Cretaceous Basin (central Europe) suggests a -400-kyr pace and a distinct asymmetry of interpreted ESL cycles. The rising limbs of ESL change constitute only 20-30 % of the cycle, and are encased entirely within the falling phase of the 405-kyr eccentricity. The intervening ESL falls (<= 6 m in magnitude) are more protracted, starting within 70 kyr prior to the eccentricity minima and culminating -60 kyr after the 405-kyr eccentricity maxima. Despite similarities to the sawtooth shape of -100-kyr glacioeustatic oscillations of the Late Pleistocene, the time scales and phasing are unparalleled in the Pleistocene icehouse. A similar, 405-kyr pace is found in ice-volume variations of the early Miocene, but the timing of glacioeustatic change relative to eccentricity forcing is incompatible with the phase of greenhouse sea-level oscillations. The phasing points to major differences in the geographic location and insolation sensitivity of the key hydrological reservoirs under icehouse and greenhouse regimes. The inferred structure of greenhouse eustasy points to low- or middle-latitude water storage, likely aquifers, that charge (expand) with rising seasonality variations and discharge (contract) with declining seasonality amplitudes on the 405-kyr scale. The net volume of water transferred on these time scales is within 2.2 x 106 km3, equivalent to <= 10 % of the present-day storage in the uppermost 2 km of continental crust. Potential additive interference with steric eustasy, proportionally relevant during greenhouse regimes, could reduce the volumes required for continental storage.

The launch traffic to Low Earth Orbit (LEO) is undergoing significant changes: instead of launching few, complex, large and expensive spacecraft, the trend is now towards the use of multitudes of small, less complex and lower-cost satellites. Large constellations, encompassing thousands of satellites in restricted regions of space, are emerging as important space assets. The intensifying commercial use of LEO and international debate regarding the stability of the space environment is a growing discussion among policy makers. Utilizing the SDM 5.0 evolutionary model developed by the Italian National Council of Research (CNR), the first step of this analysis is to estimate the growth of the space objects in LEO in the next decades. The analysis considers the space objects >10 cm, including active and defunct satellites, spent rockets bodies and fragments, along with varying future traffic, mitigation and remediation scenarios. Subsequently, the analysis focuses on the probability of collision with active satellites and on related mitigation and remediation scenarios. Based on this, the study employs a qualitative and preliminary approach to assess satellite operators' economic convenience of adopting measures that can mitigate the risk of collision by comparing their cost to the damage costs that may occur in case of collision. Finally, the study dedicate its concluding considerations to discuss if a free market setting can stimulate the formation of effective solutions to space debris challenges (namely, if it provides operators with the economic incentive to adopt or develop mitigation measures) or if public institutions' intervention is needed to finance mitigation strategies and, in particular, complex technologies development and adoption.

Hydrogen generation from water using solar energy has grown into a promising approach for sustainable energy production. Over the last years, graphitic carbon nitrides (g-C3N4, CN), polymers based on the heptazine-group, have been widely applied as photocatalysts for H2 evolution. The poor charge separation efficiency of CN is considered the major drawback. Here, we investigated the effect of coupling CN with different types of carbon nanotubes on the charge transfer properties and the photocatalytic H2 evolution. We used carbon nanotubes (CNTs) of different wall number (single (SWCNTs), double (DWCNTs) and multi-walled (MWCNTs) CNTs) for the development of full-organic CN based composite photocatalysts. Photoactivity was drastically affected by the content but more importantly by the nature of the CNTs. The SWCNTs functionalized CN composites were the most active presenting approximately 2-5 times higher H2 evolution than the corresponding DWCNTs and MWCNTs functionalized CN under both solar and pure visible light irradiation. Photoactivity was primarily controlled by the improved electronic properties linked with the abundance and stability of photogenerated charges as evidenced by electron paramagnetic resonance spectroscopy. Transient absorption spectroscopy verified the transfer of reactive electrons from CN to CNTs. CNTs functioned as electron acceptors improving charge separation. The data suggest that charge transfer is inversely proportional to the wall number of the CNTs and that photoactivity is directly controlled by the size at the nanoscale of the CNTs used. In the CNTs/CN nanocomposites, photogenerated electrons are transferred more efficiently from CN when SWCNTs are used, providing more available electrons for H2 production.

This is the longest continuous experiment where ethylenediurea (EDU) was used to protect plants from ozone (O3). Effects of long-term ambient O3 exposure (23 ppm h AOT40) on biomass of an O3 sensitive poplar clone (Oxford) were examined after six years from in-ground planting. Trees were irrigated with either water or 450 ppm EDU. Above (-51%) and below-ground biomass (-47%) was reduced by O3 although the effect was significant only for stem and coarse roots. Ambient O3 decreased diameter of the lower stem, and increased moisture content along the stem of not-protected plants (+16%). No other change in the physical wood structure was observed. A comparison with a previous assessment in the same experiment suggested that O3 effects on biomass partitioning to above-ground organs depend on the tree ontogenetic stage. The root/shoot ratios did not change, suggesting that previous short-term observations of reduced allocation to tree roots may be overestimated.