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This Article examines the genesis and context of SE4All, placing the effort within both itshistorical and international policy contexts. It highlights the voluntary nature of the initiative andargues that its effective implementation and the achievement of its goals require the articulation ofan applicable international legal framework that aids the transformation of SE4All’s policy actionsinto binding international legal commitments. The article contends that such a transformation doesnot depend on the creation of entirely new legal rules or institutions. Instead, an effective frame-work for successful implementation of SE4All can be derived from existing rules of internationalhuman rights law and sustainable development law. Reliance on these twin bodies of interna-tional law will increase the prospects for SE4All to achieve energy access and related goals thatits predecessor initiatives have failed to accomplish

Climate change has become one of the most urgent challenges facing our planet today. The consequences we are gradually experiencing have been driven by human activity. Specifically, the increase in energy demand, met mainly through the combustion of fossil fuels such as coal, oil derivatives and natural gas, has significantly increased greenhouse gas emissions, especially carbon dioxide (CO2), leading to global warming. To address the environmental problems arising from climate change, which we are gradually experiencing, it is clear that the development of the use of renewable energy sources is the key to the transition from fossil fuels to these innovative energy alternatives, in order to achieve zero emissions and contribute to decarbonization. However, the deployment of these clean energies requires the development of systems that guarantee continuous energy production, to overcome interruptions caused by the variability of natural resources like wind, sun, or water. A viable solution to this issue is employing energy storage technologies to correct the mismatch between energy supply and demand. In particular, in the specific case of the use of the sun as a renewable thermal energy source, thermal energy storage (TES) systems are of great interest, since more than half of the energy demanded in industry is thermal energy. Among the different sensible TES media, conventional concrete is emerging as a very attractive option for use as TES due to its low cost, high availability, ease of processing, high specific heat, good mechanical stability at high temperature and excellent operational performance when subjected to thermal cycling. And despite its moderate thermal conductivity, research has shown that incorporating multiple heat exchangers through which the heat transfer fluid (HTF) passes in concrete improves its efficiency, albeit at an increased cost. However, caution should be exercised in the use of concrete as the production of its precursor, Portland cement (PC), is a significant contributor to greenhouse gas emissions, particularly CO2. It is estimated that for every ton of PC produced, approximately one ton of CO2 is released into the atmosphere. For this reason, construction materials must be rethought and one of the lines of research to reduce CO2 emissions is the search for alternative precursors known as supplementary cementitious materials (SCM). SCMs enable the full or partial substitution of PC. Complete replacement of PC leads to the development of alkali-activated materials (AAM), while partial replacements, typically around 70-80%, result in the development of hybrid materials (HM). This Doctoral Thesis involves the fabrication of both alternative cementitious materials, AAM mortars and HM mortars, to investigate their feasibility as TES. Specifically, for both alternatives, the main precursor used as a substitute is blast furnace slag (BFS), an industrial by-product that has proven to be a promising alternative. In the case of the AAM mortar composed of BFS, SLAG, the activation of the precursor is carried out with sodium silicate due to the excellent mechanical properties of the final cementitious material. Nevertheless, the use of solutions makes the workability of these systems difficult, so HM with BFS (HSLAG) are also manufactured, which hydrate in the presence of water. HM mortars are composed of almost 80% BFS, about 20% PC and 5% sodium sulphate to promote the alkaline medium necessary for BFS activation. After verifying through a life cycle analysis (LCA) that alternative mortars offer benefits in terms of carbon footprint and water footprint, as well as continuing to manufacture alternatives focused on PC substitution, the possibility of replacing the natural aggregate with glass waste (GW) is investigated. The substitution of sand is carried out in the three types of mortars (AAM, HM and reference PC) with the aim of reducing water consumption, as sand is the component with the highest water demand. However, only the AAM system, SLAG, allows up to 25% of sand to be replaced by GW (SLAG75), thanks to the high cohesion of its main reaction product, the C-A-S-H gel. When the alternatives are manufactured together with the PC reference mortar, both the compressive mechanical properties and the key thermal properties for a TES, thermal conductivity and specific heat, are evaluated before and after various thermal treatments. After analyzing how the mechanical and thermal properties are affected after thermal treatments −including exposure to constant temperatures and thermal cycling−, it is determined that the alternative systems offer comparable and even superior mechanical stability under temperature exposure than a conventional PC system. In addition, alternative materials, characterized by their thermal conductivity and specific heat, show a superior suitability for TES applications compared to PC. More specifically, the AAM system, SLAG, exhibits operational characteristics superior to PC by reducing heat-up times and increasing its storage capacity, which allows for a reduction in TES volume and a reduction in heat exchanger surface area. While the HM system, HSLAG, does not reach the performance of SLAG, it does offer operational improvements compared to PC. These promising results are attributed to less degradation of the reaction products generated in the alternative mortars and better cohesion between the binder and the aggregate. This last factor had a negative effect on SLAG75, as the weakness in the bond created between the binder and the GW, as well as a greater difference in the coefficients of thermal expansion (CTE), lead to the generation of porosity, and even cracks, which determine both the mechanical and thermal behavior. Thus, when selecting a material such as TES, porosity must be controlled and evaluated as a critical parameter. The results displayed by the PC alternative systems developed in this Doctoral Thesis demonstrate their suitability to be selected as sustainable TES both at low-medium and high temperatures. Consequently, it can be generally concluded that the proposed alternative materials show a promising potential for their application as TES blocks. Thus, further research and development in this field could lead to the widespread adoption of these materials as TES, thus contributing to the transition towards sustainable and renewable energy systems.

The design that is being developed is a Water Monitoring System for Speed and Eramosa Rivers. This design consists of four sensors (turbidity, conductivity, dissolved oxygen and water level) which monitor the Speed and Eramosa Rivers in Guelph, Ontario. The sensors input measurements to a microcontroller which processes the inputs. The software contained on the microcontroller will pass a warning message to a wireless modem which relays the problem to a base station if dangerous contamination levels are reached.

A report about NOAA's budget for the year 2012. NOAA aims to detect changes in the earth's environment and protect ocean and coastal ecosystems and resources.

The world population is expected to reach an estimated 9.2 billion by 2050. Therefore, food production globally has to increase by 70% in order to feed the world, while total arable land, which has reached its maximal utilization, may even decrease. Moreover, climate change adds yet another challenge to global food security. In order to feed the world in 2050, biotechnological advances in modern agriculture are essential. Plant genetic engineering, which has created a new wave of global crop production after the first green revolution, will continue to play an important role in modern agriculture to meet these challenges. Plastid genetic engineering, with several unique advantages including transgene containment, has made significant progress in the last two decades in various biotechnology applications including development of crops with high levels of resistance to insects, bacterial, fungal and viral diseases, different types of herbicides, drought, salt and cold tolerance, cytoplasmic male sterility, metabolic engineering, phytoremediation of toxic metals and production of many vaccine antigens, biopharmaceuticals and biofuels. However, useful traits should be engineered via chloroplast genomes of several major crops. This review provides insight into the current state of the art of plastid engineering in relation to agricultural production, especially for engineering agronomic traits. Understanding the bottleneck of this technology and challenges for improvement of major crops in a changing climate are discussed.

This study analyzes the relationship between drought processes and crop yields in Moldova, together with the effects of possible future climate change on crops. The severity of drought is analyzed over time in Moldova using the Standard Precipitation Index, the Standardized Precipitation Evapotranspiration Index, and their relationship with crop yields. In addition, rainfall variability and its relationship with crop yields are examined using spectral analysis and squared wavelet coherence. Observed station data (1950–2020 and 1850–2020), ERA5 reanalysis data (1950–2020), and climate model simulations (period 1970–2100) are used. Crop yield data (maize, sunflower, grape), data from experimental plots (wheat), and the Enhanced Vegetation Index from Moderate Resolution Imaging Spectroradiometer satellites were also used. Results show that although the severity of meteorological droughts has decreased in the last 170 years, the impact of precipitation deficits on different crop yields has increased, concurrent with a sharp increase in temperature, which negatively affected crop yields. Annual crops are now more vulnerable to natural rainfall variability and, in years characterized by rainfall deficits, the possibility of reductions in crop yield increases due to sharp increases in temperature. Projections reveal a pessimistic outlook in the absence of adaptation, highlighting the urgency of developing new agricultural management strategies.

The effect of polar solvents and polar cosolvent mixtures on the transport properties of benzocaine in polydimethylsiloxane (PDMS) was studied. Methanol, ethanol, n-propanol, and n-butanol, as well as aqueous cosolvent mixtures of each n-alkanol, were used as vehicles for benzocaine. A constant activity gradient was maintained in all diffusion studies, with the membrane exposed to saturated donor suspensions of drug, and sink conditions maintained in the receiver. In spite of the constant activity gradient, steady-state benzocaine flux was substantially enhanced with increasing n-alkanol volume fraction and reached a maximum for the pure n-alkanol in each case. At any given composition, the degree of benzocaine flux enhancement generally increased with n-alkanol carbon number. In terms of the appropriate Fick's first law expression for this system, these observations were attributed to simultaneous changes in benzocaine concentration within the PDMS membrane, the diffusion coefficient of benzocaine in PDMS, fillerless membrane volume fraction, tortuosity, and the membrane thickness. These parameters were in turn correlated with the cosolvent composition in contact with the membrane. Both membrane solubility and diffusion coefficient were found to increase substantially, but decreases in tortuosity and increases in fillerless membrane volume fraction and membrane thickness were minor.

Shipping list no.: 88-266-P. ; Distributed to some depository llibraries in microfiche. ; Includes bibliographical references. ; Mode of access: Internet.