An analysis is made of the comparative efficiency of the process of separating spherical particles of finely divided loose product with different types of motion of the separating surface. The ...influence on the efficiency of the process of separation of the kinematic parameters of the motion of the screen surface is considered. A probabilistic approach to the analysis of sieving efficiency is used.
War powers Zeisberg, Mariah
2013., 20130721, 2013, 2013-07-21
eBook
Armed interventions in Libya, Haiti, Iraq, Vietnam, and Korea challenged the US president and Congress with a core question of constitutional interpretation: does the president, or Congress, have ...constitutional authority to take the country to war?War Powersargues that the Constitution doesn't offer a single legal answer to that question. But its structure and values indicate a vision of a well-functioning constitutional politics, one that enables the branches of government themselves to generate good answers to this question for the circumstances of their own times.
Mariah Zeisberg shows that what matters is not that the branches enact the same constitutional settlement for all conditions, but instead how well they bring their distinctive governing capacities to bear on their interpretive work in context. Because the branches legitimately approach constitutional questions in different ways, interpretive conflicts between them can sometimes indicate a successful rather than deficient interpretive politics. Zeisberg argues for a set of distinctive constitutional standards for evaluating the branches and their relationship to one another, and she demonstrates how observers and officials can use those standards to evaluate the branches' constitutional politics. With cases ranging from the Mexican War and World War II to the Cold War, Cuban Missile Crisis, and Iran-Contra scandal,War Powersreinterprets central controversies of war powers scholarship and advances a new way of evaluating the constitutional behavior of officials outside of the judiciary.
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•Enrichment of rare earth elements (REE) from coal and coal by-products.•Particle size, magnetic and density (float-sink) separations were investigated.•Density separation showed the ...highest enrichment of REE.•Elemental analysis suggests that REE are associated with the Al/Si group.•A combination of physical separation methods is recommended for REE enrichment.
Rare earth elements (REE) are of strategic importance because they find numerous applications in various sectors of the global economy. The concern about the REE supply challenge has led to increasing interest and research in the recovery of REE from end-of-life products and secondary sources such as coal and coal by-products. The work reported here was focused on examining the technical feasibility of physical separation techniques for the enrichment of REE from coal and coal by-products. Particle size, magnetic and density separations were performed on coal, coal ash, clay and shale samples. It was found that the samples responded to particle size separation differently. For all ash samples, higher REE concentrations were found in the finer fractions. For the clay and shale samples, however, the REE concentrations decrease as the particle size reduces possibly because RE minerals were not effectively released by grinding. Magnetic separation showed that REE are enriched in non-magnetic fractions for all ash samples. All samples responded similarly to density separation. Among the three methods, density separation showed the highest enrichment of REE. A combination of these methods is recommended. Finally, correlations between elements were demonstrated, which leads to the classification of three groups containing mainly Al/Si, Fe and Ca, respectively. REE are strongly associated with the Al/Si group.
Great efforts have been made toward the separation of CO2 from flue gas and biogas to mitigate environmental pollution and the demand for renewable fuels, respectively. Nonthermal‐based separations, ...such as adsorption‐based or membrane‐separation technology employing porous materials, are considered to be more promising than traditional cryogenic and absorption‐based systems. Due to several advantages of metal–organic frameworks (MOFs) over other conventional porous materials, reports on flue and biogas separation by MOFs are burgeoning (423 for adsorption and 56 for membrane‐based separations until June 2021) and demand urgent summarization. This review presents a bird's eye view on such separations while organizing the developed strategies and considering several performance parameters, such as trade‐off between sorption capacity and separation selectivity in adsorption‐based systems and permeability versus separation selectivity in membrane‐based systems. In addition, the mechanisms involving such separations at the molecular level are presented. A critical discussion section offers more crucial insights into these materials from industrial deployment viewpoints. Finally, future recommendations are made for further developments of MOF materials as flue and biogas separators and thus toward solving both the challenging universal problems of global warming and energy scarcity simultaneously.
This review offers a bird's eye view on the state‐of‐the‐art research of metal–organic frameworks (MOFs) for flue and biogas separation. The organization of all developed strategies to obtain the trade‐off among competing separation parameters with comprehensive discussion has been made. A critical discussion focusing on industrial requirements, challenges, and future prospects is presented.
The aim of the book is to provide an understanding of the current science underpinning Carbon Capture and Sequestration (CCS) and to provide students and interested researchers with sufficient ...background on the basics of Chemical Engineering, Material Science, and Geology that they can understand the current state of the art of the research in the field of CCS. In addition, the book provides a comprehensive discussion of the impact of CCS on the energy landscape, society, and climate as these topics govern the success of the science being done in this field.
Speech separation is the task of separating target speech from background interference. Traditionally, speech separation is studied as a signal processing problem. A more recent approach formulates ...speech separation as a supervised learning problem, where the discriminative patterns of speech, speakers, and background noise are learned from training data. Over the past decade, many supervised separation algorithms have been put forward. In particular, the recent introduction of deep learning to supervised speech separation has dramatically accelerated progress and boosted separation performance. This paper provides a comprehensive overview of the research on deep learning based supervised speech separation in the last several years. We first introduce the background of speech separation and the formulation of supervised separation. Then, we discuss three main components of supervised separation: learning machines, training targets, and acoustic features. Much of the overview is on separation algorithms where we review monaural methods, including speech enhancement (speech-nonspeech separation), speaker separation (multitalker separation), and speech dereverberation, as well as multimicrophone techniques. The important issue of generalization, unique to supervised learning, is discussed. This overview provides a historical perspective on how advances are made. In addition, we discuss a number of conceptual issues, including what constitutes the target source.
Two‐dimensional nanosheets have shown great potential for separation applications because of their exceptional molecular transport properties. Nanosheet materials such as graphene oxides, ...metal–organic frameworks, and covalent organic frameworks display unique, precise, and fast molecular transport through nanopores and/or nanochannels. However, the dimensional instability of nanosheets in harsh environments diminishes the membrane performance and hinders their long‐term operation in various applications such as gas separation, water desalination, and ion separation. Recent progress in nanosheet membranes has included modification by crosslinking and functionalization that has improved the stability of the membranes, their separation functionality, and the scalability of membrane formation while the membranes’ excellent molecular transport properties are retained. These improvements have enhanced the potential of nanosheet membranes in practical applications such as separation processes.
Modification of nanosheet membranes by crosslinking and functionalization has improved their stability, their separation functionality, and the scalability of membrane production while retaining the membranes’ excellent molecular transport properties. These improvements have enhanced the potential of nanosheet membranes in practical applications such as separation processes.
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