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Aluminum tripolyphosphate was used as a corrosion inhibitor in a simulated concrete pore solution. For studies of the inhibition mechanism of aluminum tripolyphosphate on the carbon steel, its influence on the pitting initiation on the carbon steel in a Cl⁻ containing pore solution were investigated.

Potentiodynamic polarization curves, Mott–Schottky plots and potentiostatic polarization of the carbon steel in the pore solution with different content of aluminum tripolyphosphate were measured, as well as the optical micrographs of pitting on the carbon steel was observed.

The metastable pitting potential and the stable pitting potential increased, while the donor density and the flat band potential decreased with the concentration of aluminum tripolyphosphate in solution. Furthermore, the initiation of pitting was suppressed, as well as the transition from metastable to stable pitting was hindered by the aluminum tripolyphosphate. The scale parameter (a), in the extreme distribution of the maximum current peak, could be used to predict the transition from metastable to stable pitting.

The inhibition mechanism of aluminum tripolyphosphate on carbon steel in pore solution was revealed. It suppresses the initiation of pitting and hinders the transition from metastable to stable pitting. Furthermore, a parameter defined as the scale parameter (a) in the extreme distribution of the maximum current peak was introduced to predict the transition from metastable to stable pitting.

Organic coatings are widely used for protecting metal equipment and structures from corrosion. Accurate detection and evaluation of the protective performance and service life of coatings are of great importance. This paper aims to review the research progress on performance evaluation and lifetime prediction of organic coatings.

First, the failure forms and aging testing methods of organic coatings are briefly introduced. Then, the technical status and the progress in the detection and evaluation of coating protective performance and the prediction of service life are mainly reviewed.

There are some key challenges and difficulties in this field, which are described in the end.

The progress is summarized from a variety of technical perspectives. Performance evaluation and lifetime prediction include both single-parameter and multi-parameter methods.

The purpose of this paper is to study the variations of composition and properties of the passive film on 316 L stainless steel surface in 80°C, 0.5 mol L-1 H2SO4 + 2 mg L-1 NaF solution, is helpful to understand the mechanisms of corrosion resistancethe of plated Pd on 316 L ss.

The variations of composition and properties of the passive film on 316 L stainless steel surface in 80°C, 0.5 mol L-1 H2SO4 + 2 mg L-1 NaF solution after connected to Pd electrode were studied with methods of potential monitor, X-ray photoelectron spectroscopy analysis and electrochemical impedance spectrum (EIS) measurement.

By connecting to a Pd electrode, the potential of the SS sample increased from the active region to the passive region. By connecting to the Pd electrode, the contents of Cr, Cr(OH)3 and Fe3O4 in passive film increased obviously. With increased Pd/SS area ratio, the Cr(OH)3 content in passive film increased but the Fe3O4 content changed little. The results show that after connecting to Pd the corrosion resistance of the passive film on 316 L stainless steel increases obviously, which may be attributed to the more compact passive film because of higher Cr, Cr(OH)3 and Fe3O4 contents and less point defects in the film.

The effects and mechanism of Pd on passivation of SS was studied.

The purpose of this paper is to improve the operation and maintenance intelligence of power systems, and summarize the transmission line robots and their key technologies. High-voltage power cables are important channels for power transmission systems. Their special geographical environment and harsh natural environment can lead to many different faults. At present, such special operations in dangerous and harsh environments are performed manually, which have not only high labor intensity and low work efficiency but also great personal safety risks.

For maintenance works that are far away from the tower, power outages are required. With the increasing evaluation of transmission quality and operational safety, and the urgent need for automation and operation of modern power systems, the contradiction between this manual operation and modern high-quality power transmission has become increasingly prominent. An effective method to replace the manual maintenance work is to use the mobile robot to carry the operation manipulator and its end tool, that is, the live maintenance robot.

Some achievements have been made in the key technologies of live maintenance robots, the work to be done to meet the basic requirements of complex and changeable line environment and practical application. Based on the existing research results of live overhaul robot, the follow-up research will focus on the practical application needs and the frontier of scientific and technological development, and truly realize the human–machine integration between live overhaul robot–human working environment. Only in this way can the robot better serve the operation and maintenance of the power system.

This paper reviews the system platform, operation function, structural characteristics and key technologies involved in the power cable robot, and the combination of live maintenance robots and modern high-tech such as big data and cloud computing is also given, and finally, the future development direction of the special operation robot is pointed out.

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.

Contractor selection is critical in green buildings (GBs) since the preferred contractor has the responsibility to achieve construction sustainability as well as relationship sustainability. The developer satisfaction reflecting requirements can boost the cooperative relationship among stakeholders and act as an evaluation scale for the success of GB projects, which needs to be emphasized in the selection process but little involved in the existing research. This study explores improving GB contractor (GBC) selection by integrating developer satisfaction into selection procedures.

A systematic framework of GBC selection including twenty-five criteria from literature review and experts survey is firstly constructed. Both tactical and strategic criteria are further classified into Kano categories (must-be, one-dimensional, and attractive categories) using the fuzzy Kano model (FKM), and weighted by the developer satisfaction index. The model proposed by this study combining FKM and TOPSIS divides the selection process into the filtration phase and selection phase by Kano categories. The proposed model is finally verified through performance comparison among multiple methods in a case.

Selection criteria are measured linearly and nonlinearly, showing criteria having nonlinear satisfaction change accounts for two-thirds of all. Criteria at tactical level tend to be must-be or one-dimensional categories for the developer, and most strategic criteria are classed as the attractive category, indicating that adding strategic criteria is necessary for long-term cooperation. The proposed model, using developer satisfaction to improve the selection process, ensures the selected GBC to be the most satisfactory with requirements of the developer and makes the performance of GBCs easily distinguishable.

This study contributes to the existing body of knowledge for promoting relationship sustainability by supplementing an integrated model with emphasis on developer satisfaction in GBC selection, so as to establish a good initial foundation due to the match between performances of GBCs and needs of developers. It not only helps maximize developer satisfaction in GBC selection by applying satisfaction to pre-construction management, but also instructs GBCs to prioritize performance improvements. The framework is also conducive for developers to classify selection criteria and select other participants (like green suppliers) from the satisfaction perspective in GBs.

This study aims to gain an understanding of success factors and barriers to public private collaboration in the context of zero emission neighbourhood.

Qualitative research method: narrative literature study.

On the basis of the identified success factors and barriers, a model with the following five interconnected themes is developed: (1) supportive public policy, (2) stakeholder management, (3) creation of a common ground for understanding, (4) knowledge sharing and learning and (5) uncertainty management.

The model can be further developed and tested. In-depth conceptual/empirical study on the five themes can shed more light on the topic.

This model is one of the several ways to understand, structure and simplify the reality (of public private collaboration in the context of zero emission neighbourhood). These five themes are arranged in the model in such a way to represent strategic, tactical and operational levels. This model can be useful to identify measures (steps, concrete actions, etc.) To address issues related to the five themes in a given organisational context. Focusing adequately on these five themes can contribute to successful public private collaboration in the context of zero emission neighbourhoods.

This study/model provides an overall, holistic approach to address/improve public private collaborative endeavours in the context of developing zero emission neighbourhoods.

The idea of implementing supply chain management (SCM) principles for the construction industry was embraced by construction stakeholders to enhance the sector's performance. The analysis from the literature revealed that the implementation of SCM in the construction industry enhances the industry's value in terms of cost-saving, time savings, material management, risk management and others. The construction supply chain (CSC) can be managed using the pull or push system. This chapter also discusses the origin and proliferation of SCM into the construction industry. The chapter revealed that the concept of SCM has passed through five different eras: the creation era, the use of ERP, globalisation stage, specialisation stage and electronic stage. The findings from the literature revealed that we are presently in the fourth industrial revolution (4IR) era. At this stage, the SCM witnesses the adoption of technologies and principles driven by the 4IR. This chapter also revealed that the practice of SCM in the construction industry is centred around integration, collaboration, communication and the structure of the supply chain (SC). The forms and challenges hindering the adoption of these practices were also discussed extensively in this chapter.

Infill materials play a pivotal role in determining buildings’ life cycle costing (LCC) and environmental impacts. International standards prescribe LCC and life cycle assessments (LCA) to assess materials’ economic and environmental sustainability. The existing methods of LCC and LCA are tedious and time-consuming, reducing their practical application. This study sought to integrate LCC and LCA with building information modeling (BIM) to develop a swift and efficient approach for evaluating the life cycle performance of infill materials.

The BIM model for a case study was prepared using Autodesk Revit®, and the study included four infill materials (lightweight aggregate concrete block (LECA), autoclaved cellular concrete (AAC), concrete masonry and bricks). LCC was conducted using Revit® and Autodesk Insight 360® to estimate costs incurred across different project phases. LCA was conducted using “One Click LCA®,” a BIM-based platform featuring a comprehensive material inventory. Carbon emissions, acidification, and eutrophication were chosen as environmental impact factors for LCA.

LECA was the preferred choice due to its lower cost and environmental impact. Its lifetime cost of $440,618 was 5.4% lower than bricks’, with 2.8% lower CO₂ emissions than AAC’s, which were second-place options, respectively. LECA had 6.4 and 27% lower costs than concrete blocks, and AAC’s carbon emissions were 32 and 58% lower than concrete blocks and bricks, respectively.

BIM has been employed for life cycle analysis in existing literature, but its efficacy in evaluating the lifetime costs and environmental impacts of infill materials remains unexplored. The current study presents a BIM-based approach for conducting LCC and LCA of infill materials, facilitating informed decision-making during the planning phase and promoting sustainable construction practices.

The kindergarten curriculum in mainland China has evolved through four periods and the current reform began in the end of 1980s. The reform aimed to transform kindergarten practice by shaping ideologies including respect for individual child, active learning, and play-based integrated curriculum. This review of research literatures shows that compared with the practice before the reform, many kindergarten teachers organize classrooms in learning centers, provide more play materials, pay time, and freedom for free play, and pay more attention to individuals. But indoor space organized in rice-seedling-bed model, teacher-led group instruction and teacher-controlled interactions are still often observed after three decades of reform efforts; there still exist great variations among kindergartens of different sponsoring bodies and in different regions. The problems resulted from the innate deficiencies of the top-down and value-priority reform, the conflicts between the advocated value and the traditional Chinese culture with emphasis on Ming-Fen, testing, and the value of children for the whole family and nation, and the unequal distribution of public resources decided by the educational institutions. Therefore, the curriculum reform is not a separate endeavor from other social changes, but a comprehensive and systematic change. To guarantee the success of the curriculum reform, the Chinese society needs cultural transformation and institutional reconstruction.