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As an efficient, safe, and environmentally friendly technology, semiconductor photocatalysis has been widely used in the removal of antibiotics from wastewater. In this work, a novel Ag/BiOI/g‐C3N4 composite photocatalytic material, BiOI/g‐C3N4, g‐C3N4, and BiOI are prepared as the photocatalysts. The morphologies, chemical properties, and photocatalytic performances of the photocatalysts are characterized using scanning electron microscope, transmission electron microscope, X‐ray diffraction, X‐ray photoelectron spectroscopy, Fourier‐transform infrared spectrometer, ultraviolet–visible spectroscopy (UV–Vis) diffuse reflectance spectra, and photoluminescence spectra. In addition, tetracycline hydrochloride (TC) and ceftiofur sodium aqueous solutions are used to simulate wastewater and the photocatalytic degradation performances of the photocatalysts are investigated and compared under visible light. Compared to g‐C3N4, BiOI, and BiOI/g‐C3N4, the Ag/BiOI/g‐C3N4 demonstrates superior performance, increasing the removal rates of TC and ceftiofur sodium to 85.6% and 90.2%, respectively. The photocatalytic mechanism of the Ag/BiOI/g‐C3N4 may involve the promotion of the visible light–harvesting ability and inhibition of the recombination of photogenerated electron/hole pairs. Furthermore, the primary active groups in the system are identified as superoxide radicals (·O2−) and hydroxyl radicals (·OH). Herein, some valuable insights into the development of innovative photocatalytic materials are offered for the effective removal of antibiotics from water. [ABSTRACT FROM AUTHOR]

The Belt and Road (B&R) initiative creates a highly competitive and dynamic environment and cooperation network for construction projects in specific regions. By using the experience of other countries, construction professionals can be well-equipped with management skills for solving intractable problems during the project management process of a construction project. Value management (VM) is a systematic team decision-making methodology used to achieve the best project value, but it is rarely applied in developing regions along the B&R. This study aims to identify critical success factors for the implementation of VM in construction projects in both developed and developing regions along the B&R. Six focus groups targeting three groups of regions were conducted, including advanced VM developed regions (Regions 1), advanced VM developing regions (Regions 2), and unadvanced VM developing regions (Regions 3). Three main groups of critical success factors were identified by using contextual analysis: technical process, team behaviors, and outcomes. By comparing VM in advanced VM regions (Regions 1 and Regions 2) and traditional team decision-making in unadvanced VM regions (Regions 3), the study revealed that (1) practitioners in Regions 1 applied VM to achieve project success with a logical process and positive team behaviors, although several problems were also encountered; (2) surprisingly, in some technical respects, VM practitioners in Region 2 performed better than those in Regions 1, but positive team behaviors were still not emphasized; and (3) inefficient traditional decision-making activities with illogical technical processes and negative team behaviors in Regions 3 often led to poor project outcomes. A propositional model is established based on the identified critical success factors and comparison results among the three groups of regions. Finally, several practical recommendations are proposed to ensure effective VM application and promotion in both developed and developing regions along the B&R. In the developing countries that participated in the Belt and Road initiative, poor performance is not uncommon for megaconstruction projects with multiple stakeholders due to poor problem-solving strategies. This research revealed that value management practitioners in developed regions could achieve good project outcomes by applying value management with a logical framework and positive team behaviors, but they have not yet found a good way to resolve problems in terms of time constraints, no follow-up actions, and duplicate information from the public. VM practitioners in some of the developing regions put much effort into VM application, but the poor function analysis and insufficient conflict management, commitment, and transparency still impacted the final project outcomes negatively. Various problems such as no information analysis, serious corruption, and limited participation were encountered in illogical traditional team decision-making activities in developing regions, which significantly destroyed stakeholder outcomes and project performance. This research explores the insufficient value management practices in both developed and developing regions along the B&R, which provides empirical evidence to constriction professionals to update their VM/traditional team decision-making strategies and find out the best ways to conduct VM logically and effectively for improving final project outcomes. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to prepare ZnFe2O4 nanospheres, sheet MoS2 and three ZnFe2O4@MoS2 core-shell composites with various shell thicknesses, and add them to the base oil for friction and wear tests to simulate the wear conditions of hybrid bearings. Design/methodology/approach: Through the characterization and analysis of the morphology of wear scars and the elemental composition of friction films, the tribological behavior and wear mechanism of sample materials as lubricant additives were investigated and the effects of shell thickness and sample concentration on the tribological properties of core–shell composite lubricant additives were discussed. Findings: The findings demonstrate that each of the five sample materials can, to varying degrees, enhance the lubricating qualities of the base oil and that the core–shell nanocomposite sample lubricant additive has superior lubricating properties to those of ZnFe2O4 and MoS2 alone, among them ZnFe2O4@MoS2-2 core–shell composites with moderate shell thickness performed most ideally. In addition, the optimal concentration of the ZnFe2O4@MoS2 lubricant additive was 0.5 Wt.%, and a concentration that was too high led to particle deposition and affected the friction effect. Originality/value: In this work, ZnFe2O4@MoS2 core–shell composites were synthesized for the first time using ZnFe2O4 as the carrier and the lubrication mechanism of core–shell composites and single materials were compared and studied, which illustrated the advantages of core–shell composite lubricant additives. At the same time, the influence of different shell thicknesses on the lubricant additives of core–shell composites was studied. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2022-0367/ [ABSTRACT FROM AUTHOR]

According to the redox ability of dopamine in a weak alkaline environment, silver nanoparticles were uniformly loaded on the surface of polydopamine-modified graphene oxide (Ag/PGO). The results show that the base oil containing Ag/PGO nanoparticles exhibits a better tribological property than base oil. The maximum decrease in wear rate and friction coefficient at different temperatures amounted to 68% and 53.6%, respectively. The tribofilm containing C, O, N, and Ag exists and plays an important role in reducing friction and increasing wear resistance. Molecular dynamics simulations show that the microscopic oil film composed of Ag/PGO and n-hexadecane has low shear deformation during the shearing process, and the oil film has low interaction energy with the upper and lower shear walls. [ABSTRACT FROM AUTHOR]