•Compound of ZnMn2O4 spheres anchored on jute porous carbon has been synthesized.•The composite material possessed a capacity of 1501.6 mA h g-1 after 200 cycles at 0.2 C.•At 2 C, it still has a ...capacity of 701.9 mA h g-1, and no capacity loss of 1000 cycles.
Compound of ZnMn2O4 spheres anchored on jute porous carbon has been synthesized via a template method and a facile hydrothermal method. The composite material has possessed a capacity of 1501.6 mA h g−1 after 200 cycles at a current density of 0.2 C. At a current density of 2 C, it still has a capacity of 701.9 mA h g−1, and no capacity loss of 1000 cycles. Display omitted
As anodes of lithium-ion batteries, transition metal oxide materials have been considerably studied due to their high theoretical specific capacities. However, their poor conductivities and the disintegration of their structures due to volume changes when charging and discharging have restricted the development of transition metal oxide anode materials in lithium-ion batteries. In this work, a novel ZnMn2O4 sphere/jute porous carbon composite material is prepared and displays a high capacity of 1501.6 mA h g−1 after 200 cycles at a current density of 0.2 C (1 C = 784 mA g−1). At a current density of 2 C, it still has a capacity of 701.9 mA h g−1 and no capacity loss for 1000 cycles. The reason for this excellent cycling stability is that the anode material has formed a special structure of ZnMn2O4 spheres composited with jute biomass porous carbon during the preparation process. Biomass porous carbon can promote charge transfer and reduce the volume change of ZnMn2O4. This work proposes an approach to prepare an environmentally friendly, high-performance lithium-ion battery anode material.
The international trade regulatory system is a dynamic system that has been evolving throughout its history. Tension and conflict are part of the system. While calls for the abolition of the ...principal trade regulation authority, the WTO, have failed to understand this nature of the system, proponents for reforms have so far not paid sufficient attention to the evolving nature of tension and conflict. This book examines the evolving dynamics in international trade regulation from the conclusion of GATT in 1947 to the current crisis facing the WTO, from a perspective of emerging powers of developing countries with a focus of China as the latest force that demands reforms of the international trade regulatory regime.There is an extensive body of scholarship on ideological struggles, the rise of developing countries, geopolitical contest, the emerging powers (especially China), the use, misuse or abuse of trading rules and so on. There is, however, a lack of a single concise research book that synthesises these underlying causes and factors into a coherent and precise analytical theme. This book attempts to fill this research gap by building upon the existing scholarship and placing the various tensions and conflicts in a perspective that treats them as dynamic factors that have propelled a continuing process of evolution of the international trade regulation.The book will interest those researching on international trade regulation as well as development studies.The Open Access version of this book, available at www.taylorfrancis.com, has been made available under a Creative Commons Attribution-Non-Commercial-No Derivatives 4.0 license.
The international trade regulatory system is a dynamic system that has been evolving throughout its history. Tension and conflict are part of the system. While calls for the abolition of the ...principal trade regulation authority, the WTO, have failed to understand this nature of the system, proponents for reforms have so far not paid sufficient attention to the evolving nature of tension and conflict. This book examines the evolving dynamics in international trade regulation from the conclusion of GATT in 1947 to the current crisis facing the WTO, from a perspective of emerging powers of developing countries with a focus of China as the latest force that demands reforms of the international trade regulatory regime. There is an extensive body of scholarship on ideological struggles, the rise of developing countries, geopolitical contest, the emerging powers (especially China), the use, misuse or abuse of trading rules and so on. There is, however, a lack of a single concise research book that synthesises these underlying causes and factors into a coherent and precise analytical theme. This book attempts to fill this research gap by building upon the existing scholarship and placing the various tensions and conflicts in a perspective that treats them as dynamic factors that have propelled a continuing process of evolution of the international trade regulation. The book will interest those researching on international trade regulation as well as development studies.
How self-renewal versus differentiation of neural progenitor cells is temporally controlled during early development remains ill-defined. We show that mouse Lin41 (mLin41) is highly expressed in ...neural progenitor cells and its expression declines during neural differentiation. Loss of mLin41 function in mice causes reduced proliferation and premature differentiation of embryonic neural progenitor cells. mLin41 was recently implicated as the E3 ubiquitin ligase that mediates degradation of Argonaute 2 (AGO2), a key effector of the microRNA pathway. However, our mechanistic studies of neural progenitor cells indicate mLin41 is not required for AGO2 ubiquitination or stability. Instead, mLin41-deficient neural progenitors exhibit hyposensitivity for fibroblast growth factor (FGF) signaling. We show that mLin41 promotes FGF signaling by directly binding to and enhancing the stability of Shc SH2-binding protein 1 (SHCBP1) and that SHCBP1 is an important component of FGF signaling in neural progenitor cells. Thus, mLin41 acts as a temporal regulator to promote neural progenitor cell maintenance, not via the regulation of AGO2 stability, but through FGF signaling.
Understanding the overall catalytic activity trend for rational catalyst design is one of the core goals in heterogeneous catalysis. In the past two decades, the development of density functional ...theory (DFT) and surface kinetics make it feasible to theoretically evaluate and predict the catalytic activity variation of catalysts within a descriptor-based framework. Thereinto, the concept of the volcano curve, which reveals the general activity trend, usually constitutes the basic foundation of catalyst screening. However, although it is a widely accepted concept in heterogeneous catalysis, its origin lacks a clear physical picture and definite interpretation. Herein, starting with a brief review of the development of the catalyst screening framework, we use a two-step kinetic model to refine and clarify the origin of the volcano curve with a full analytical analysis by integrating the surface kinetics and the results of first-principles calculations. It is mathematically demonstrated that the volcano curve is an essential property in catalysis, which results from the self-poisoning effect accompanying the catalytic adsorption process. Specifically, when adsorption is strong, it is the rapid decrease of surface free sites rather than the augmentation of energy barriers that inhibits the overall reaction rate and results in the volcano curve. Some interesting points and implications in assisting catalyst screening are also discussed based on the kinetic derivation. Moreover, recent applications of the volcano curve for catalyst design in two important photoelectrocatalytic processes (the hydrogen evolution reaction and dye-sensitized solar cells) are also briefly discussed.
A self-consistent mathematic elucidation of the origin of volcano curve was conducted by a two-step kinetic model analytically, and some interesting guidelines for catalyst design are discussed during our derivation.
We have developed an approach by combining machine-learning model and genetic algorithm to tackle the challenge for locating stable bimetallic clusters and the atomic distribution. It achieved quick ...DFT-level prediction of PES of PtmAu38-m clusters, and the most stable composition and preferential atomic distribution rule were identified and understood.
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Bimetallic nanoparticles (AmBn) usually exhibit rich catalytic chemistry and have drawn tremendous attention in heterogeneous catalysis. However, challenged by the huge configuration space, the understanding toward their composition and distribution of A/B element is known little at the atomic level, which hinders the rational synthesis. Herein, we develop an on-the-fly training strategy combing the machine learning model (SchNet) with the genetic algorithm (GA) search technique, which achieve the fast and accurate energy prediction of complex bimetallic clusters at the DFT level. Taking the 38-atom PtmAu38-m nanoparticle as example, the element distribution identification problem and the stability trend as a function of Pt/Au composition is quantitatively resolved. Specifically, results show that on the Pt-rich cluster Au atoms prefer to occupy the low-coordinated surface corner sites and form patch-like surface segregation patterns, while for the Au-rich ones Pt atoms tend to site in the core region and form the core-shell (Pt@Au) configuration. The thermodynamically most stable PtmAu38-m cluster is Pt6Au32, with all the core-region sites occupied by Pt, rationalized by the stronger Pt-Pt bond in comparison with Pt-Au and Au-Au bonds. This work exemplifies the potent application of rapid global search enabled by machine learning in exploring the high-dimensional configuration space of bimetallic nanocatalysts.
China has changed and the continuing changes have not just been about economic development. Among the many transformations there has been another quiet, peaceful, and largely successful (but far from ...perfect) 'revolution' in the area of law, whose deficiencies have been more often mercilessly examined and documented than have its historical achievements and significance. This legal 'revolution' is the subject matter of the present book. Like the previous edition in 2008, it examines the historical and politico-economic context in which Chinese law has developed and transformed, focusing on the underlying factors and justifications for the changes. It attempts to sketch the main trends in legal modernisation in China, offering an outline of the principal features of contemporary Chinese law and a clearer understanding of its nature from a developmental perspective. It provides comprehensive coverage of topics: 'legal culture' and modern law reform, constitutional law, legal institutions, law-making, administrative law, criminal law, criminal procedure law, civil law, property, family law, contracts, torts, law on business entities, securities, bankruptcy, intellectual property, law on foreign investment and trade, Chinese investment overseas, dispute settlement and implementation of law. Fully revised, updated and considerably expanded, this edition of Chinese Law: Context and Transformation is a valuable and important resource for researchers, policy-makers and teachers alike.
The first-principles DFT calculations together with microkinetic analysis reveal the complex catalytic mechanism of low-content NO oxidation on CrO2(110) at room temperature. It quantitatively makes ...clear that CrO2(110) can exhibit considerable activity with the Mars-van-Krevelen mechanism preferred, and the nitrate species serves as the key poisoning species.
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The NO oxidation processes on CrO2(110) was investigated by virtue of DFT + U calculation together with microkinetic analysis, aiming to uncover the reaction mechanism and activity-limiting factors for CrO2 catalyst. It was found that NO oxidation on CrO2(110) has to be triggered with the lattice Obri involved (Mars-van Krevelen mechanism) rather than the Langmuir-Hinshelwood path occurring at the Cr5c sites alone. Specifically, the optimal reaction path was identified. Quantitatively, the microkinetic analysis showed that CrO2(110) can exhibit a high turnover rate of 0.978 s-1 for NO oxidation at room temperature. Such an activity could originate from the bifunctional synergetic catalytic mechanism, in which the Cr5c sites can exclusively adsorb NO and the Obri is very reactive and provides oxidative species. However, it is worth noting that, as the reactive Obri tightly binds NO2, the nitrate species was found to be difficult removed and constituted the key poisoning species, eventually limiting the overall activity of CrO2. This work demonstrated the considerable catalytic ability of CrO2 for NO oxidation at room temperature, and the understanding may facilitate the further design of more active Cr-based catalyst.
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