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Metal-Organic Framework with Immobilized Nanoparticles
Published in Anish Khan, Mohammad Jawaid, Abdullah Mohammed Ahmed Asiri, Wei Ni, Mohammed Muzibur Rahman, Metal-Organic Framework Nanocomposites, 2020
Neslihan Karaman, Kemal Cellat, Hilal Acıdereli, Anish Khan, Fatih Şen
The use of MOF-based materials for nanostructures, energy storage, and conversion are important by effectively immobilizing active functional materials and improving material properties. There are remarkable improvements in energy applications based on MOFs, composites, and derivatives [5]. Unlike known storage systems, hydrogen is known to be physically adsorbed in storage environments either chemically or by weak van der Waals interactions. Hydrogen can be stored in carbon nanotubes by physical adsorption and in an MOF with a high surface area. Functionalization of MOFs with various nanoparticles (NPs) is an effective way to strengthen. A typical hydrogen energy system consists of following parts: production of hydrogen from renewable sources, storage of high volumes in low volumes, and the realization of hydrogen energy conversion with high efficiency [6–8]. The optimal calcination process with the rational combination and production of MOF precursors works synergistically to improve MOF performance. Considering environmental damage caused by fossil fuels and low-efficiency energy transformations, it is inevitable to search for systems that use renewable energy sources that perform energy conversion with higher efficiency in the future [9]. MOFs are a kind of three-dimensional porous material. MOFs are well suited for hydrogen storage due to their advantages, including structural diversity, functionality, ease of loading, and reverse laying applications [10] (Figure 11.1).
The World’S Energy Problem And Carbon Dioxide Emissions—The Conversion Of Primary Energy
Published in Kojima Toshinori, Harrison Brian, The Carbon Dioxide Problem, 2019
Toshinori Kojima, Brian Harrison
The differences between the various groups of countries are analyzed in Fig. 3.3, which also includes much more recent data (including the later increase in energy use after the fall in the price of crude oil). Taking the 1971 level of carbon emissions as 100, Fig. 3.3 shows subsequent changes with respect to per capita economic growth and to population; there seems to be a strong correlation between carbon dioxide emissions and economic growth. Furthermore, changes are seen both due to energy conversion (i.e. a change in the amount of carbon dioxide produced per unit of energy, or ‘carbon intensity’) and to energy conservation (i.e. the amount of energy needed per unit of economic activity, or ‘energy intensity’). Energy conversion refers to a change from one type of energy to another. A change from thermoelectric power to nuclear power, or certain changes in the type of thermoelectric power employed (e.g. from oil-fired power stations to ones using natural gas), would lead to a reduction in the amount of carbon dioxide produced; conversely, conversion from oil to coal would increase the quantity of carbon dioxide formed. Energy conservation includes not only increased efficiency of energy use but also structural changes (such as a move away from energy-intensive industries); this might, for example, involve a change from manufacturing to knowledge-intensive industries.
Computational Fluid Dynamics Study of Serpentine Flow Field Proton Exchange Membrane Fuel Cell Performance
Published in C. S. P. Rao, G. Amba Prasad Rao, N. Selvaraj, P. S. C. Bose, V. P. Chandramohan, Mechanical Engineering for Sustainable Development, 2019
Venkateswarlu Velisala, G. Naga Srinivasulu
The ever-increasing energy demand, emission-free energy generation, and other ecological issues have encouraged many researchers to look for advanced efficient energy conversion technologies.1 Within such a perspective, fuel cell (FC) systems may be considered as a good alternative due to practical merits such as the high-energy density, superb dynamic response, low hostility to the environment, and lightweight as well as easy and fast recharging through a replacement or a refilled fuel cartridge.2 FCs are categorized based on the type of electrolyte materials.3 The commonly available FC technologies include polymer electrolyte membrane (PEMFC), alkaline (AFC), phosphoric acid (PAFC), molten carbonate (MCFC), and solid oxide (SOFC)-based FCs.
Calculation model of dissipated thermal energy of anthracite impact crushing, incorporating cooling process and spatial temperature distribution
Published in International Journal of Coal Preparation and Utilization, 2023
Qing Guo, Yongtai Pan, Qiang Zhou, Chuan Zhang, Yankun Bi, Ziwei Zhuang, Yuping Zhang
A violent energy conversion occurred at the moment of crushing, and the kinetic energy of the drop weight was converted into the elastic deformation energy of the specimen, the dissipated thermal energy, the kinetic energy of the splashing particles, and other forms of energy. However, due to the shadow of the drop weight, the infrared camera cannot directly record the temperature distribution of the crushed specimen at this moment. And the temperature field of the crushed specimen can only be obtained when the hammer was lifted and taken out of the field of view. During the lifting of the hammer, the temperature of the high-temperature particles generated by the crushing process will decrease to some extent. For accurate calculation, the calculation model has to consider the temperature drop caused by this cooling process. Since the hammer was pulled up right after the occurrence of crushing, the high-temperature particles were in a state of natural convection during this process. The temperature of each high-temperature particle at the moment of crushing was calculated following Newton’s cooling law.
Working Performance and Feasibility Evaluation of Four-stroke Compressed Air Engine
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Existing studies illustrate that the second law of thermodynamics is the main theoretical method to study the energy conversion process and efficiency of the CAE. The researchers have also been conducting research on the application of CAE vehicles for future green vehicles to realize the sustainable development of society and the environment. Nevertheless, in terms of the technology itself, CAEs are currently only suitable as power sources for short-distance urban transportations, and their ranges and efficiencies are still key issues that need to be addressed. Since 2018, the authors have been carrying out a series of systematic studies on the working characteristics, energy utilization, port timing, and tests of the CAE, and have obtained some important research results in (Ramasubramanian et al. 2020; Zeng and Xu 2020, 2022; Zeng, Xu, and Zhao 2019). Table 1 summarizes the different torques studied recent 4 years by different authors. A careful look at the CAE designs proposed by different authors reveals that the torque of CAE or CAE vehicle involved in the current research results is not high making its practical application difficult and challenging. This paper aims to provide solutions for the research and development of high-torque CAE, and promote the design and development of CAEs.
Fusion Gain and Triple Product for the Sheared-Flow-Stabilized Z Pinch
Published in Fusion Science and Technology, 2023
U. Shumlak, E. T. Meier, B. J. Levitt
Conventional power gain in electronic or microwave circuits, for example, is defined as the ratio of output power to input power,[19] even when considering components or subcircuits, e.g., amplifiers. Unity gain indicates an electronic circuit with an output power equal to the input power. This power gain contrasts with the definition of fusion gain given by Eq. (3), which subtracts the input power from the output power in the numerator. The input power that leaves the plasma volume is expected to be recaptured. Radiative power would be absorbed by the surrounding blanket of working fluid in a power reactor. Similarly, the power associated with thermal energy and kinetic energy leaves the plasma volume and may also be recovered by heating the blanket or be extracted as kinetic energy for direct energy conversion or space propulsion applications. A scientific power gain for a fusion core that aligns with the definition of conventional power gain could be expressed as