This research implements sustainable environmental practices by repurposing post-industrial plastic waste as an alternative material for non-conventional construction systems. Focusing on the development of a recycled polymer matrix, the study produces panels suitable for masonry applications based on tensile and compressive stress performance. The project, conducted in Portoviejo and Medellín, comprises three phases combining bibliographic and experimental research. Low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene (PP) were processed under controlled temperatures to form a composite matrix. This material demonstrates versatile applications upon cooling—including planks, blocks, caps, signage, and furniture (e.g., chairs). Key findings indicate optimal performance of the recycled thermoplastic polymer matrix at a 1:1:1 ratio of LDPE, HDPE, and PP, exhibiting 15% deformation. The proposed implementation features 50 × 10 × 7 cm panels designed with tongue-and-groove joints. When assembled into larger plates, these panels function effectively as masonry for housing construction, wall cladding, or lightweight fill material for slab relieving.

In order to explore the influence of the ferroelectric surface on the structure and properties of semiconductor oxides, the growth of CdS nanocrystals was regulated and controlled by taking single-crystal perovskite PbTiO₃ nanosheets as the substrate through a simple hydrothermal method. Through composition design, a series of PbTiO₃-CdS nanocomposite materials with different loading concentrations were prepared, and their microstructure and photocatalytic properties were systematically analyzed. Studies show that in the prepared product, CdS nanoparticles selectively grow on the surfaces of PbTiO₃ nanosheets, and their morphology is affected by the exposed surfaces of PbTiO₃ nanosheets. There is a clear interface between the PbTiO₃ substrate and CdS nanoparticles. The concentration of the initial reactant and the time of hydrothermal reaction also significantly affect the crystal morphology of CdS. Photocatalysis studies have shown that the prepared PbTiO₃-CdS nanocomposite material has a significant degradation effect on 10 mg/L of Rhodamine B aqueous solution. The degradation efficiency rises with the increase of CdS loading concentration. When degrading 10 mg/L Rhodamine B aqueous solution, the PbTiO₃-CdS sample with a mass fraction of 3% can reach a degradation rate of 72% within 120 min.

This paper analyzed the equitable allocation of infrastructure across regional states in Ethiopia. In general, in the past years, there has been a good start in the infrastructure sector in Ethiopia. However, the governance and equity system of infrastructure in Ethiopia is not flexible, not technology-oriented, not fair, and not easily solved. The results of in-depth interviews and focus group discussions (FGDs) showed that there is a lack of institutional capacity, infrastructure governance, and equity, which has negatively impacted the state- and nation-building processes in Ethiopia. According to the interviewees, so long as the unmet demand for infrastructure exists, it remains a key restrain on doing business in most Ethiopian regional states. This is due to the lack of integrated frameworks, as there are coordination failures (lack of proper government intervention, including a lack of proper understanding and implementation of the constitution and the federal system). In Ethiopia, to reduce these bottlenecks arising from the lack of institutional capacity, infrastructure governance, and equity and their effects on nation-building, first of all, the government has to critically hear the people, deeply assess the problems, and come to the point and then discuss the problems and the way forward with the society at large.

Developing Asia’s infrastructure gap results from both inadequate public resources and a lack of effective channels to mobilize private resources toward desired outcomes. The public-private partnership (PPP) mechanism has evolved to fill the infrastructure gap. However, PPP projects are often at risk of becoming distressed, or worst, being terminated because of the long-term nature of contracts and the many different stakeholders involved. This paper applies survival-time hazard analysis to estimate how project-related, macroeconomic, and institutional factors affect the hazard rate of the projects. Empirical results show that government’s provision of guarantees, involvement of multilateral development banks, and existence of a dedicated PPP unit are important for a project’s success. Privately initiated proposals should be regulated and undergo competitive bidding to reduce the hazard rate of the project and the corresponding burden to the government. Economic growth leads to successful project outcomes. Improved legal and institutional environment can ensure PPP success.

Starting from the ‘90s, there has been a significant increase in PPP use in the public sector in Europe, benefiting the implementation of infrastructure projects. In Italy, PPP is still much more limited than in such countries as the UK and France: the projects funded are smaller and the sectors involved are less appropriate. Based on the economic literature, European initiatives and international comparisons, the paper examines aspects of regulations that could encourage the appropriate use of PPP and considers the problems with the Italian regulations, while proposing some corrective measures. The main limitations involve: i) the absence of adequate preliminary assessments about the advantages of using PPP rather than the traditional procurement, ii) the relative lack of attention to the contract terms, iii) inadequate safeguards to ensure the bankability of the projects, and iv) limited information transparency and accessibility.