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[en] Titanium and titanium pigments have very good potential growth in India with the demand surging in the end use sectors. The country has substantial raw materials and the wherewith al to produce. So is the case with zirconium. However, challenges include meeting environmental issues related to mining and also the need to obtain state of the art technologies for cleaner and cost-efficient processing. In this article, a detailed scenario is presented along with production and demand situation, the new projects on the anvil and application areas. (author)
[en] Drought is the primary cause of yield loss in agriculture throughout the world and is currently the most common reason for global food shortages and food insecurity. The estimated cost of drought across Africa over the period of 2014 to 2017 totalled USD$ 372 billion. Climate change is expected to increase drought severity and its negative effect. The impact of drought is particularly severe in Sub-Saharan Africa (SSA) where rainfed subsistence farming dominates food production and the social and economic disaster management systems are usually inadequate. An increase in crop yields is required to meet the needs of a growing population.The aim of the project is to use induced genetic variation for mutation breeding with the use of optimal phenotyping systems to improve cowpea adaptation to drought. It is expected to lead to the release of high-yielding cowpea varieties tolerant to drought stress.
[en] We analyzed the effect of the use of Eye Protective Equipment (EPE) and the best position to use individual dosimeters to estimate the eye lens radiation dose to a medical staff that works with yttrium-90. Three Alderson-Head-Phantoms were exposed to 58 MBq of Y for 24 h, in two different experiments: (1) at different dosimeter placements and (2) with and without the use of EPE. The measurements were carried on by thermoluminescent technique. Doses received by dosimeters on both lenses were more closely represented by the ones placed between the eyes than those on the temples, which underestimated the doses by a factor of 3. Also, the transmission factors showed that the EPE was able to reduce the H(3) values from about 78% to 92%. This study demonstrated that the use of EPE can optimize the Y eye lens dose. An individual dosimeter should be worn between the eyes for an appropriate estimate of this equivalent dose.
[en] The development of metal oxide-based electron transport layers in perovskite solar cells (PSCs) has received intensive research interest for achieving high-efficiency PSCs. Herein, TiO nanorods (TiO NRs) are grown on TiO seed layers coated on fluorine-doped tin oxide (FTO) glass substrate by using a hydrothermal method and then are utilized as the electronic transport layer in PSCs. The main concern, after hydrothermal growth of TiO NRs, is that their crystallinity can be improved by a sequential high-temperature treatment at 450 °C. In addition to high-temperature annealing, a low-temperature treatment with boiling water, which is expected to clean the surface of the TiO NRs, is developed. In this contribution, the champion PSCs are those based on TiO NRs where boiling water treatment achieves a maximum power conversion efficiency (PCE) of 15.50%, whereas a PCE of 12.91% is obtained from PSCs based on TiO NRs with high-temperature annealing. The remarkable ease of using a water-assisted process offers an efficient approach to the removal of residuals adsorbed on the surface and circumvents the disadvantage of a thermal annealing method resulting in high-production costs. This low-temperature treatment can be used to improve TiO films in flexible PSCs. (© 2020 Wiley‐VCH GmbH)
[en] A CIRED team has just published a study on how to meet the demand for electricity without nuclear or fossil fuels. She concluded that it would not cost more than it does today. With the hypotheses of the cost of wind power and photovoltaics that it has retained, it is also possible to calculate that it would cost less than with new nuclear reactors. In addition to the costs of wind and photovoltaic production, the CIRED study retains a set of explicit or implicit assumptions which deserve to be commented on the level of electric power consumption, the stability of the network, the efficiency of the storage means, the reception by the population of tens of thousands of wind turbines and thousands of square kilometers of photovoltaics, the consumption of critical materials and dependence on foreign countries, the loss of a nuclear know-how that the world will need, the vulnerability of an electrical network based on digital communications.
[fr]Une equipe du CIRED vient de publier une etude sur la facon de repondre a la demande d'electricite sans nucleaire ni energie fossile. Elle conclut que cela ne couterait pas plus cher qu'aujourd'hui. Avec les hypotheses de cout de l'eolien et de photovoltaique qu'elle a retenues on peut aussi calculer que cela couterait moins cher qu'avec des nouveaux reacteurs nucleaires. Outre les couts de production eolien et photovoltaique, l'etude du CIRED retient un ensemble d'hypotheses explicites ou implicites qui meritent d'etre commentees sur le niveau de consommation d'electricite, la stabilite du reseau, l'efficacite des moyens de stockage, l'accueil par la population de dizaines de milliers d'eoliennes et de milliers de kilometres carre de photovoltaique, la consommation de materiaux critiques et la dependance a l'egard de l'etranger, la perte d'un savoir faire nucleaire dont le monde aura besoin, la vulnerabilite d'un reseau electrique reposant sur les communications numeriques. (auteur)
[en] While France and a growing number of countries around the world have been setting ambitious goals for reaching net-zero emissions, variable renewables like wind and solar energy are set to become the main building blocks in power systems worldwide as countries seek to decarbonise their economies. In a new joint analysis commissioned by the French Ministry for the Ecological Transition, the IEA (International Energy Agency) and RTE (Reseau de Transport d'Electricite) describe four essential areas that policy makers must address when wind and solar PV start to dominate electricity generation. The new report, Conditions and requirements for the technical feasibility of a power system with a high share of renewables in France towards 2050, outlines four groups of strict conditions that need to be met to integrate very high shares of renewables in a technically secure way in a large and meshed power system such as that of France. - Power system strength: Even if they still need to be proven at large scale, there is a general scientific consensus that technological solutions to maintain system strength - and therefore stability - without conventional generation exist in several cases. Specific difficulties are expected in the case of a system with a significant share of distributed solar PV. Further assessment of the impacts of distributed PV on the power distribution network and their implications for electricity security is needed. - System adequacy: This is the ability of a power system to cope with a given load at all times. It can be ensured even in a system mainly based on variable renewables as long as substantial sources of flexibility are available, including demand-response, large-scale storage, peak generation units and well-developed transmission networks and interconnections. The maturity, availability and cost of different flexibility mixes need to be evaluated in further analysis. - Operational reserves: The sizing of these reserves and the regulatory framework for balancing responsibilities and procurement would need to be substantially revised in a large power system as such that of France. Moreover, forecasting methods for variable renewables would need to be continually improved. - Grid development: Substantial efforts would be necessary beyond 2030 at both transmission and distribution levels. This requires strong proactive steps and public engagement in long-term planning in order to assess costs and work with citizens on social acceptance of new infrastructure. These efforts can nonetheless be partly integrated into the renewal of ageing network assets. The joint study marks an important step and is part of a larger work program aimed at developing and comparing scenarios for the long-term transformation of the electricity system to achieve carbon neutrality by 2050. On 27 January 2021, RTE will open a public consultation assessing the framework and assumptions of these future scenarios, and will present the conclusions of this consultation in the Fall 2021.