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By adding a Ce salt and an Nd salt to an anodizing electrolyte, modified anodic films are obtained on aluminum surfaces. This paper aims to study the effects of rare‐earth elements on the corrosion resistance of the anode film.

The crystalline film was studied by X‐ray diffraction. The methods of scanning electron microscope, energy dispersive X‐ray analysis, electrochemical polarization, and electrochemical impedance spectroscopy (EIS) were used to characterize the properties of the films.

After rare‐earth element modification, the pores of the porous layer were very evidently smaller, the anodic film was more compact, and the thickness and hardness of the films had increased. The corrosion resistance of the anodic films modified with rare‐earth elements clearly was improved in neutral, acidic, and basic NaCl solutions. Ce showed a better effect than Nd in increasing the corrosion resistance of the films, and the film modified with Ce+Nd showed the highest corrosion resistance. EIS analysis showed that the impedances of both the barrier layer and porous layer of the anodic films increased after modification with the rare‐earth elements, indicating that the anodizing process was affected by the presence of the rare‐earth elements.

The results presented in this paper offer a foundation for further research and application of rare‐earth elements in aluminum anodic oxide films.

The aluminide and CeO₂ and La₂O₃ containing aluminide coatings on carbon steel have been prepared by a pack cementation process. The influence of CeO₂ and La₂O₃ additions on the oxidation rates of aluminide coatings has been investigated. The performance of coatings was studied by measuring oxidation kinetics, metallography, SEM and X‐ray diffraction analysis techniques. The oxidation‐resistance of coated carbon steel is discussed on the basis of a decrease in oxidation rates as well as adherence of oxide scales. The oxidation rates of carbon steel and aluminide coatings were markedly reduced in the presence of CeO₂ and La₂O₃ in the temperature range of 700‐900°C. The oxidation rates were significantly affected by the morphology of oxide scales. In the case where the structure of oxides scales was not seriously disrupted due to decarburisation, the oxidation rates were significantly reduced.

This paper aims to elucidate the geochemical characteristics of the hydrothermally altered rocks with gold mineralization and the elemental transfers in hydrothermal alteration hosted in alkaline complex in Hongshan area, Taihang Orogen, North China, and preliminarily discuss the relationship between the gold mineralization and the hydrothermal alteration.

Based on detailed field investigation, sampling and petrographical observation, major oxides and trace elements of nine rock samples are analyzed, and the method of mass balance equation is used in calculation of the elemental transfer.

Three alteration stages in the Hongshan area are identified, which are the early, main and late alterations. The early one is characteristic of extensive pyritization in the complex, which is related to the mantle-derived magmas and occurs before gold mineralization. The main one is characterized by developing a great deal of altered rock in fracture zones with the gain of many elements and the loss of a few elements. The late one is dominated by limonitization, that is limonite replacing the early pyrite or Fe₂O₃ replacing FeO in rocks. In the main alteration, the altered rocks obviously gain fluid component (LOI, i.e. loss on ignition) and elements such as V, As, Rb, Au, La, Ce and Nd and total rare earth elements (REEs). Elements such as K, Fe, Cu, Zn, Y, Mo, Sb, W, Re and U are gained in some altered rocks. Na and Sr are lost in all altered rocks, and Th and Bi are lost in some ones in the meantime. The following elements: Si, Mg, Mn, Ca, Li, Sc, Cr, Co, Ni, Zr, Ag, Ba and Hg show either gain or loss in different altered rocks. Au is notably enriched in the hydrothermal alteration. The elemental gain or loss in the altered rocks indicates that the main mineralization develops extensive de-alkalinization, local potassic metasomatism, silicification or desilicification.

The purpose of this paper is to provide an update to the Supply Chain Volatility Index (SCVI), and expand on prior work by presenting a conceptual framework illustrating how firms can deal with persistent volatility, the ensuing risk and mitigate the cost implications for their supply chain operations.

The authors use long-term time series of secondary data to assemble a “basket” of key indicators that are relevant to the business context within which global supply chains operate. The authors also report on five years of feedback gained from presentations of the SCVI to scholars and practitioners.

Volatility has reduced from record levels experienced during the global financial crises, yet remains at levels considerably higher than prior to the crisis, with no sign of a return to the more stable conditions that prevailed when many current supply chain networks were designed.

The authors reaffirm that new mental models are needed which embrace volatility as a factor in supply chain design, rather than seek to eradicate it in supply chain operations. Traditional static “network optimisation” based on a simple definition of low unit cost seems no longer appropriate under conditions of persistent volatility.

The authors provide a conceptual link of volatility, risk and cost in the supply chain, and outline how firms can develop a supply chain strategy by managing their exposure to volatility.

The authors challenge the common assumption that volatility invariably leads to risk and higher cost in the supply chain. Instead the authors argue that the supply chain structure can mitigate the exposure to supply chain risk. The authors introduce the concepts of recovery and resilience cost within a framework designed to help firms manage volatility-induced risk by minimising the adverse cost implications of volatility in their supply chains.

Scientific research is producing ever‐increasing amounts of quantitative data worthy of communication to scholars, but more than can be accommodated in refereed publications even though the number of journals is itself increasing. In the last twenty years, the quantity of geochemical analytical data produced world‐wide has increased a hundredfold or more. Geochemical and petrological journals nowadays rarely publish the complete sets of data; instead, only selected representative data are published and the remainder may or may not be put into supplementary publications. In the last five years, a scheme has been set up in the UK which co‐ordinates geochemical publications with a growing computerised geochemical data bank. The data bank comprises not only the geochemical analytical data actually printed on the journal pages but also the remainder of the data set pertaining to the published paper which could not be printed for lack of space. In collaboration with the journal editor, the data are collected into the data bank at the same time as the author is submitting his or her paper for publication. The author enters the data in a standard format and sends them as hard copy or in machine‐readable form to the data bank editor. The editor verifies the data and passes them for archiving to the National Geochemical Data Bank manager of the British Geological Survey whence they can be retrieved. The data are also relayed to the World Data Center for storage and further distribution.

Smart materials (SMs) have the potential for facilitating active disassembly (AD). Select SMs are used in the design of devices to aid product disassembly. The purpose of this paper is to compare different AD approaches and highlight future work and potential.

This work is a survey of the collated AD research employing only Smart and “made Smart” materials work from various published work in the field from companies and academia since its original invention. The introduction gives general discussion of AD with cost implications and how the technology could offer very lean dismantling. An overview of the history of the work is given with the context of the implications for the need for a technology like AD to retain critical materials.

Besides a survey to date, comparisons were made of each AD technology application highlighting advantages and challenges. Comparisons were also made prior to this in alternative disassembly strategies to give context to the potential usefulness of the technology.

Only AD with SMs or “made Smart” were highlighted with some considerations for potential candidates.

A survey of AD work only employing SMs and “made‐Smart” materials to date. Comparisons of each AD application were made highlighting advantages and challenges. Comparisons were made between AD and alternative disassembly strategies to give context to the potential usefulness of the technology. The conclusion included an overview of work with consideration for future work. A candidate technology with the most potential was discussed.

China holds a global monopoly of up to 97 percent for rare earth elements (REEs), which are indispensable for all kinds of twenty-first century high-tech applications. Since China has disrupted its exports and started discriminating between domestic and foreign demand, REEs have become a geostrategic resource. In March 2012, Japan, the USA and the European Union jointly filed a World Trade Organization dispute settlement case against China. The purpose of this paper is to elaborate why China implemented export quotas and tariffs on REEs and how the state is engaged in this sector domestically and abroad.

The analysis frames China as a “competition state” and connects domestic with foreign economic policy on REEs. It uses data from Chinese official documents and non-Chinese sources.

Better government control aims to consolidate the sector and lay the foundation for three other goals, namely: the establishment of integrated and innovative Chinese corporations that compete globally; the provision of incentives to attract high-tech foreign direct investment to China; and better environmental protection. China wants to climb the next step of the technological ladder to gain global economic leadership.

Global environmental protection in mining is eased. However, non-Chinese market players can only take advantage of new business opportunities when the prices remain high. Since REEs are of strategic importance, rising political interference and raw materials diplomacy will continue to distort markets and price building.

The paper connects domestic reregulation of China's rare earth sector with foreign policy goals (or “going in” and “going out”) using the competition state approach.

Before documentary information can be used, a complex series of operations have to take place: 1. information must be recorded in documents, 2. each document must be stored with others in some accessible place and its location known, 3. characteristic aspects of each document must be identified, to form a document profile, and this must be recorded with others in some file, 4. the potential user must formulate some query or express some interest in terms of characteristics recorded about documents, 5. this user profile must be compared with document profiles and the locations of matching documents identified, 6. the documents themselves must be located and presented to the user.

Rare earths are essential materials for many high-tech industries critical to both economic development and national defense. China, the world's dominant supplier of rare earths, has recently been imposing stricter controls over its production and export. The purpose of this paper is to examine the domestic roots of the changes in China's rare earth industry production and exports in its three-decade rise to the current global monopoly.

This paper adopts the historical institutionalism approach to analyze the trajectory of industry and trade development. The author analyzes data collected from government whitepapers and reputed scholarly and news sources.

This paper argues that the Chinese rare earth industry has gone through three periods of development, in which the state attempted to control the market and industry through reformulating rules and institutions to achieve state goals. Domestic state institutions, combined with macroeconomic environment and state governance strategy shaped the three-decade experience of rare earth industry and trade development in China.

This paper builds on existing findings about Chinese state regulations to provide a novel analytical framework to analyze the role of the state in industry and trade development in the rare earth industry. The focus on a single strategic industry seldom studied in the current literature also provides ample empirical value to further scholarly understanding about this industry.