Fluoride-rich phosphogypsum leachate is a challenging industrial wastewater because of its low pH, high ionic strength, and the presence of competing anions. In this study, lanthanum-modified activated alumina (La-AA) was prepared and evaluated as a selective adsorbent for the removal of fluoride from complex phosphate-industry wastewater. The results showed that La modification improved the adsorption performance of activated alumina, and the 10% La-AA sample exhibited the best fluoride removal behavior among the tested materials. Kinetic and thermodynamic analyses indicated that fluoride adsorption on La-AA was more favorable than on pristine activated alumina and proceeded spontaneously and endothermically under the tested conditions. In competitive adsorption tests, La-AA maintained better fluoride uptake than unmodified activated alumina in the presence of chloride, sulfate, and phosphate, demonstrating improved matrix tolerance. When applied to authentic phosphogypsum leachate, the optimized La-AA reduced fluoride concentration from 9.67 mg·L−1 to 0.58 mg·L−1, below the WHO guideline value. These results suggest that La modification is a practical strategy to improve the selectivity and applicability of activated alumina for fluoride removal in complex industrial process water.
This paper presents a review of studies devoted to the synthesis, characterization, structure, properties, and functionality of grafted silica/polyacrylamide “core-corona” hybrids as effective nanoreactors and silver nanoparticle (AgNP) carriers for modern nanotechnologies. The evidence and features of direct low-temperature radical polymerization of acrylamide from the unmodified surface of SiO2 nanoparticles are considered in the context of the manifestation of dynamic matrix effects. A simple and reliable method for determining the number and length of grafted PAAm chains is indicated. Using a number of hybrid samples, the effect of these parameters on the particle size, surface charge, height, and permeability of the PAAm “corona” is demonstrated. A two-level fractal structure of hybrids in the bulk state and two morphological forms of their particles in aqueous solutions are established. Based on the proposed approach, the kinetics, mechanism of in situ synthesis, and the yield of AgNPs in hybrid solutions are characterized depending on the concentration of reagents and the “corona” structure. Considerable attention is paid to the possible application of AgNP/hybrid nanocomposites in promising nanotechnologies: in the production of biocidal hygienic materials and textiles, in wound healing, agriculture, fish farming and poultry farming, as well as anti-cancer agents.
This study defines environmental tax as a flexible policy instrument that promotes the green and efficient transformation of agricultural production and enhances agricultural innovation productivity; in line with China’s institutional context, it is continuously measured using pollution discharge fees before 2018 and Environmental Protection Tax revenue after the implementation of the Environmental Protection Tax Law in 2018. This paper uses panel data from 30 provinces in China to empirically test the magnitude, direction, and mechanism of environmental taxes on the development of agricultural innovation productivity using a two-way fixed effects model, heterogeneity test model, mediation effect model, moderation effect model, and threshold effect model. The study finds that environmental taxes can significantly promote the development of agricultural innovation productivity. Furthermore, by analyzing geographical locations and functional Positioning of Agricultural Production, it is found that environmental taxes exhibit differentiated characteristics in driving agricultural innovation productivity; Mediation effect tests revealed that environmental taxes promote agricultural innovation productivity by suppressing agricultural carbon emissions; moderation effect tests showed that agricultural industrial structure upgrading plays a positive moderating role in the promotion of agricultural innovation productivity by environmental taxes; The threshold analysis identifies a single carbon-emission threshold: when agricultural carbon emissions exceed the threshold, the productivity-enhancing effect of environmental tax becomes stronger. Heterogeneity tests further show that the effect is most evident in central China and major grain-producing areas, while the western region faces stronger compliance-cost pressure. The study contributes by integrating the compliance-cost, Porter-hypothesis, and nonlinear-threshold perspectives into one agricultural setting and by clarifying the policy boundary under which environmental taxation can foster agricultural innovation productivity.
As the construction industry shifts toward industrialization, digitalization, intelligence, and low-carbon development, prefabricated intelligent construction has emerged as a key pathway for enhancing efficiency, quality control, resource utilization, and full life-cycle management. Yet existing studies remain largely confined to single-technology applications, local process optimization, or isolated engineering cases, lacking a systematic grasp of the field’s development trajectory, knowledge structure, research hotspots, and future challenges. Addressing this gap, this study presents a bibliometric review aimed at clarifying the research evolution, core knowledge domains, technological frontiers, and application-oriented challenges in prefabricated intelligent construction. Based on the Web of Science Core Collection, 583 journal articles published from 2015 to 2025 were retained after standardized search and screening. Using VOSviewer and bibliometrix, the study analyzed publication trends, subject distribution, national and institutional collaboration, author networks, keyword co-occurrence, thematic clustering, and research frontiers. Compared with traditional narrative reviews, this approach integrates quantitative bibliometric analysis with thematic content interpretation, constructing a panoramic and dynamic analytical framework for the field. Research shows that prefabricated intelligent construction underwent a leap from initial exploration to rapid expansion during 2015–2025, with publications and citations from 2023–2025 accounting for 76.16% and 84.07% of the total sample, respectively, establishing it as an active research frontier. In the global landscape, China contributes prominently in output volume, while Australia, the United States, the United Kingdom, and Germany demonstrate relatively high per-publication impact. The disciplinary structure is dominated by engineering, construction, and building technology, supported by multidisciplinary intersections, forming three major research hotspots: the integration of prefabricated construction and intelligent technologies, process innovation and intelligent equipment, and structural performance and engineering applications. In essence, this field represents a full life-cycle construction paradigm arising from the deep coupling of industrialization, digitalization, intelligence, and performance control. Future breakthroughs are needed in four dimensions: full life-cycle data standards, digital twin-driven closed-loop platforms, equipment–process collaborative optimization, and multi-scenario engineering validation to drive the transition toward large-scale application.
