123 research outputs found
Взаємодія вітамінів В1 і В2 у біосинтезі їх коферментних форм у щурів
Білим щурам лінії Вістар внутрішньочеревно вводили
окремо або в різних співвідношеннях вітаміни В1
і В2
та
вимірювали вплив кожного з них на інтенсивність біосинтезу коферментної форми іншого. Встановлено, що для
даної пари вітамінів (В1
і В2
) існує за цим показником оптимальне співвідношення: за вагою 6:1, за молярністю —
5:1. При цьому були використані дози вітамінів, близькі
до фізіологічних (або терапевтичних).The Wistar line white rats were introduced individually
or in different ratios vitamins В1
and В2
and measured the
influence each of them on intensity of biosynthesis of coenzyme form of the other. It is established that there is an
optimum ratio according to this index for this pair of vitamins
В1
and В2
: after the weight 6:1, after the molarness — 5:1.
The doses of vitamins close to physiological (or therapeutic)
were used
Традиція жанру лагю в живописі: Тара Зелена у супроводі вчителів школи н'їнгма
The adoption of energy efficiency measures can significantly reduce industrial energy use. This study estimates the future industrial energy consumption under two energy demand scenarios: (1) a reference scenario that follows business as usual trends and (2) a low energy demand scenario that takes into account the implementation of energy efficiency improvement measures. These scenarios cover energy demand in the period 2009-2050 for ten world regions. The reference scenario is based on the International Energy Agency World Energy Outlook (2011 edition) up to 2035 and is extrapolated by Gross Domestic Product projections for the period 2035-2050. According to the reference scenario, the industrial energy use will increase from 105 EJ in 2009 to 185 EJ in 2050 (excluding fuel use as a feedstock). It is estimated that, with the adoption of energy efficient technologies and increased recycling, the growth in industrial energy use in 2050 can be limited to 140 EJ, an annual energy use increase of 0.7 % compared with the 2009 case. The 2050 industrial energy use in the low energy demand scenario is estimated to be 24 % lower than the 2050 energy use in the reference scenario. The results of this study highlight the importance of industrial energy efficiency by providing insights of the energy savings potentials in different regions of the world
Microgrids:experiences, barriers and success factors
Although microgrids have been researched for over a decade and recognized for their multitude of benefits to improve power reliability, security, sustainability, and decrease power costs for the consumer, they have still not reached rapid commercial growth. The main aim of this research is to identify the common barriers and ultimate success factors to implementing a microgrid in the real world. We found that microgrids vary significantly depending on location, components, and optimization goals, which cause them to experience different types of challenges and barriers. However, the most common barriers were identified and grouped into four categories: technical, regulatory, financial, and stakeholder, based on the literature and overlying patterns recognized amongst the thirteen case studies. The most common technical barriers include problems with technology components, dual-mode switching from grid-connected to island mode, power quality and control, and protection issues. There is extensive research on how to overcome these issues, so technical solutions are becoming available yet case specific. Regulatory barriers exist due to interconnection rules with the main grid and the prohibition of bi-directional power flow and local power trading between microgrid and the main network. The latter issue is the barrier experienced most often and has only recently been addressed, so solutions need further research. The main financial barrier is still the burden of high investment and replacement costs of the microgrid. This can be resolved with proper market support in the short term and might naturally resolve itself through learning over the long run. Lastly, stakeholder barriers include issues with conflicting self-interest and trust, and having the expertise to manage operations. These stakeholder barriers are not yet addressed in the literature and need to be further researched
Історія України в англомовних дослідженнях 30-40-х рр. ХХ ст.
Стаття присвячена аналізу рецепції української історії в британській та американській історіографії 30-40-х рр. XX ст. Розглядаються основні праці з української історії, їх зміст, ідеологія,
вплив на подальший розвиток англомовної україніс тики.The article is devoted to analyzing the perception of Ukrainian
history in the Britannic and American historiography of the 30-40th
XX c. The main works on Ukrainian history as well as their contents,
ideology and influence on the subsequent development of Englishlanguage
Ukrainian studies are considered
Modeling the cement industry in integrated assessment models: Key factors for further improvement
Energy models, such as Integrated Assessment Models (IAMs), are widely used in the forecasting of energy consumption and greenhouse gas (GHG) emissions and in the analysis and evaluation of the different GHG mitigation options. To construct efficient industry specific policies it is important to make careful estimations of the potentials for energy and GHG savings and the associated costs of mitigation that take into account the individual characteristics of the sector. However, many energy models are lacking on technological detail with many of them assessing the industry as a whole with only limited sub-sector division. In this analysis, the main parameters in modeling the cement industry, such as cement demand drivers, production technology representation and retrofitting options, were identified and a number of simple methodological modeling improvements were composed to assist the less detailed models incorporate more bottom-up sectoral information. Some of the improvements were implemented by two IAMs, POLES and IMAGE. Initial results obtained after the implementation of a number of suggested improvements showed the importance of using recent data that take into account recent industrial developments to construct the baseline and data that take into account regional differences
Flexibility options in a decarbonising iron and steel industry
The decarbonisation of the iron and steel industry is expected to significantly increase its electricity consumption due to higher levels of electrification and the partial shift to hydrogen as iron reductant. With its batch processes, this industry offers large potential for the application of demand response strategies to achieve electricity cost savings. Previous research has primarily focused on investigating the demand response potential for currently operating manufacturing processes and partly for future low-carbon processes. This study aims to consolidate this knowledge and apply it to a modelling analysis that investigates the demand response potential of two new low-carbon technologies: the hydrogen-based direct reduction of iron with electric arc furnace technology (H2-DRI-EAF) and the blast furnace basic oxygen furnace technology retrofitted with carbon capture (BF-BOF-CCUS). A cost optimisation approach is applied to plant configurations with varying parameters relevant for flexibility, such as electrolyser and storage sizes, and in the context of future electricity prices. Multiple price profiles are selected to encompass uncertainties on the development of the power system. The potential for a H2-DRI-EAF plant is 3–27 times higher than for a BF-BOF-CCUS, with electricity costs savings potentials of 35% and 3%, respectively. The study finds that electricity prices have the most significant impact on the profitability of investing in electrolyser overcapacities, which enable operating costs reduction. Therefore, the profitability of these investments are strongly dependent on future power system configurations.</p
Flexibility options in a decarbonising iron and steel industry
The decarbonisation of the iron and steel industry is expected to significantly increase its electricity consumption due to higher levels of electrification and the partial shift to hydrogen as iron reductant. With its batch processes, this industry offers large potential for the application of demand response strategies to achieve electricity cost savings. Previous research has primarily focused on investigating the demand response potential for currently operating manufacturing processes and partly for future low-carbon processes. This study aims to consolidate this knowledge and apply it to a modelling analysis that investigates the demand response potential of two new low-carbon technologies: the hydrogen-based direct reduction of iron with electric arc furnace technology (H2-DRI-EAF) and the blast furnace basic oxygen furnace technology retrofitted with carbon capture (BF-BOF-CCUS). A cost optimisation approach is applied to plant configurations with varying parameters relevant for flexibility, such as electrolyser and storage sizes, and in the context of future electricity prices. Multiple price profiles are selected to encompass uncertainties on the development of the power system. The potential for a H2-DRI-EAF plant is 3–27 times higher than for a BF-BOF-CCUS, with electricity costs savings potentials of 35% and 3%, respectively. The study finds that electricity prices have the most significant impact on the profitability of investing in electrolyser overcapacities, which enable operating costs reduction. Therefore, the profitability of these investments are strongly dependent on future power system configurations.</p
Flexibility options in a decarbonising iron and steel industry
The decarbonisation of the iron and steel industry is expected to significantly increase its electricity consumption due to higher levels of electrification and the partial shift to hydrogen as iron reductant. With its batch processes, this industry offers large potential for the application of demand response strategies to achieve electricity cost savings. Previous research has primarily focused on investigating the demand response potential for currently operating manufacturing processes and partly for future low-carbon processes. This study aims to consolidate this knowledge and apply it to a modelling analysis that investigates the demand response potential of two new low-carbon technologies: the hydrogen-based direct reduction of iron with electric arc furnace technology (H2-DRI-EAF) and the blast furnace basic oxygen furnace technology retrofitted with carbon capture (BF-BOF-CCUS). A cost optimisation approach is applied to plant configurations with varying parameters relevant for flexibility, such as electrolyser and storage sizes, and in the context of future electricity prices. Multiple price profiles are selected to encompass uncertainties on the development of the power system. The potential for a H2-DRI-EAF plant is 3–27 times higher than for a BF-BOF-CCUS, with electricity costs savings potentials of 35% and 3%, respectively. The study finds that electricity prices have the most significant impact on the profitability of investing in electrolyser overcapacities, which enable operating costs reduction. Therefore, the profitability of these investments are strongly dependent on future power system configurations
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