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Malachite is one of the most important copper-bearing oxide minerals; however, it shows poor floatability prior to sulfidization under the thiol collector system. This study investigated the reasons for the low recovery of malachite flotation without sulfidization. The results of adsorption capacity and contact angle test indicated that the malachite surface could adsorb a sufficient amount of the collector, obviously increasing the hydrophobicity of the malachite surface under static conditions. By measuring the amount of inorganic carbon in the flotation solution, it was found that the amount of inorganic carbon in the solution increased significantly when the thiol collectors were added into pulp, which could be attributed to the induced dissolution of the malachite surface by thiol collectors. Solubility tests further demonstrated that the copper ions released from the natural dissolution of malachite proved difficult in regard to reactions with thiol collector to form precipitates; however, the thiol collector induced the dissolution of malachite surface, and so the hydrophobic complexes' copper-collector could not firmly adsorb on the mineral surface. Fourier transform infrared (FTIR) analysis revealed that thiol collectors do not adsorb stably on malachite surfaces. This was considered to be a substantial reason for the poor performance of malachite flotation without sulfidization. [ABSTRACT FROM AUTHOR]

Forest microclimates can contrast substantially from the macroclimate outside forests. These microclimates regulate understory biodiversity and ecosystem functions. Studies have quantified the global patterns and driving factors of forest understory temperature offsets, but data from China were almost missing, making the global assessment incomplete. To fill this knowledge gap, we quantitatively synthesized 494 paired observations from China extracted from 91 publications to quantify mean (Tmean), maximum (Tmax) and minimum temperature offsets (Tmin). Results showed that (1) forest canopies significantly buffered understory Tmean and Tmax against macroclimatic temperature, with average offsets of 1.0 and 1.5°C, respectively, while understory Tmin offsets were not significantly different from zero; (2) forest type (broadleaved, mixed, vs. coniferous) and forest location (rural vs. urban) did not affect Tmean, Tmax or Tmin offsets, but climate zone and season showed significant impacts; and (3) macroclimatic temperature, wind speed, tree height and canopy density also impacted temperature offsets, although their effects varied among Tmean, Tmax and Tmin. Our results complement the global assessment of forest buffering capacity, and reiterate the necessity for incorporating microclimatic variability into future bioclimatic modelling of species demography and distributions. [ABSTRACT FROM AUTHOR]

• A model comprising C/N/S-related bioprocesses was developed and evaluated. • Impact of H 2 S on MBfR/granular bioreactor performing anammox/n-DAMO was assessed. • H 2 S content in inflow gas (v/v: 0∼5%) did not significantly affect MBfR. • Influent H 2 S of granular bioreactor lowered TN removal or increased energy demand. The coupling between anammox and nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) has been considered a sustainable technology for nitrogen removal from sidestream wastewater and can be implemented in both membrane biofilm reactor (MBfR) and granular bioreactor. However, the potential influence of the accompanying hydrogen sulfide (H 2 S) in the anaerobic digestion (AD)-related methane-containing mixture on anammox/n-DAMO remains unknown. To fill this gap, this work first constructed a model incorporating the C/N/S-related bioprocesses and evaluated/calibrated/validated the model using experimental data. The model was then used to explore the impact of H 2 S on the MBfR and granular bioreactor designed to perform anammox/n-DAMO at practical levels (i.e., 0∼5% (v/v) and 0∼40 g/S m3, respectively). The simulation results indicated that H 2 S in inflow gas did not significantly affect the total nitrogen (TN) removal of the MBfR under all operational conditions studied in this work, thus lifting the concern about applying AD-produced biogas to power up anammox/n-DAMO in the MBfR. However, the presence of H 2 S in the influent would either compromise the treatment performance of the granular bioreactor at a relatively high influent NH 4 +-N/NO 2 −-N ratio (e.g., >1.0) or lead to increased energy demand associated with TN removal at a relatively low influent NH 4 +-N/NO 2 −-N ratio (e.g., <0.7). Such a negative effect of the influent H 2 S could not be attenuated by regulating the hydraulic residence time and should therefore be avoided when applying the granular bioreactor to perform anammox/n-DAMO in practice. [Display omitted] [ABSTRACT FROM AUTHOR]

Steel structures often experience significant durability degradation over time due to extreme environments. To better understand the impact of chloride environments on the mechanical properties of steel compression members, accelerated corrosion tests were conducted on H-shaped steel short columns with applied current. Monotonic tensile tests were also performed on steel specimens, and axial compression tests were carried out on H-shaped steel short columns with varying degrees of corrosion. The results revealed that the corrosion rate increased with higher current intensity and longer electrification duration while changing with different chloride ion concentrations. As the corrosion rate increased, the steel material exhibited a linear decrease in yield strength, ultimate strength, and elastic modulus. Consequently, the mechanical properties of the H-shaped steel columns, such as stiffness, ductility coefficient, and load-bearing capacity, were adversely affected. Based on these findings, a predictive formula was proposed to estimate the ultimate load-bearing capacity of H-shaped steel columns with different degrees of corrosion in chloride salt environments. The experimental results were further validated through numerical simulations, and parameter analysis indicated a negative correlation between flange width-to-thickness ratio, web height-to-thickness ratio, and ultimate load-bearing capacity of H-shaped steel columns. Finally, a random corrosion pit generation algorithm is proposed, effectively simulating the actual corrosion pit distribution and calculating the ultimate bearing capacity of columns. • The deterioration model for mechanical properties with corrosion ratio and various parameters in accelerated corrosion tests, demonstrating a linear relationship. • Secondary development of Abaqus software using Python language to randomly generate corrosion pits on the surface of the model, making the numerical simulation results more accurate. • A random corrosion pit generation algorithm is proposed to simulate the actual corrosion pit distribution and obtain the ultimate bearing capacity. [ABSTRACT FROM AUTHOR]

Being a problem that has long plagued the field of electrochemical machining process, real-time and high precision monitoring of the interelectrode gap is a difficult task. In this research, we introduce a method for monitoring the interelectrode gap using a tool electrode equipped with an optical fiber sensor. This method does not require large numbers of parameters such as conductivity of the electrolyte, electric current density distribution, shape of the electrodes, etc. and therefore reduces the complexity of the monitoring system. The optical fiber, moving together with the tool, forms an open Fabry-Pérot interferometer consists of a reflection surface of the fiber end and a reflection surface of the workpiece. Additionally, we introduce a spectrum analysis method specifically designed for the Fabry-Pérot interferometer spectrum. This method provides the absolute distance between the optical fiber and the target, demonstrating robustness to noise and abrupt spectrum changes. Consequently, it can be utilized in harsh environments for high-precision distance monitoring, a task challenging for traditional methods using optical interferometers. With the proposed method, a difference of ±2.5 μm was achieved compared with demodulating the spectrum manually. The average process time of a spectrum with 16,001 sampling points and a distance resolution of 1 nm is 0.148 s. Real-time monitoring and control of an electrochemical machining process was also implemented. The interelectrode gap was successfully maintained at 200 ± 5 μm throughout the machining process and the final machining depth measured by the proposed method and an optical measurement system has a difference of 6 μm. [ABSTRACT FROM AUTHOR]

• Investigated the impact of industrial robot adoption on GTFP in Chinese cities. • Employed the NDDF-GLPI and Bartik IV approach to estimate GTFP and the penetration of industrial robots. • Utilized a combination of two-way fixed effects models, mechanism analysis models, and quantile regression models for causal identification. • Industrial robot adoption enhances GTFP through energy saving, technological innovation, scale output, and industrial linkage. • The positive effect of industrial robots on GTFP is mitigated in areas with high pollution, while it is reinforced in regions with the development of green finance. This study investigates the impact of industrial robot adoption on Green Total Factor Productivity (GTFP) against the backdrop of increasing demand for both robot proliferation and green development utilizing urban panel data from Chinese cities spanning 2007–2019. Findings reveal that industrial robot adoption significantly improves GTFP, exerting its influence through mechanisms such as energy saving, technological innovation, scale output, and industrial linkages. Certain market factors moderate the influence of industrial robot on GTFP. Initially, regions reliant on high-pollution industries and resource-based cities experience minimal effects, which may diminish or even reverse as GTFP improves. Additionally, the positive influence of industrial robots on GTFP is particularly noticeable in regions with advanced development in green finance. This research is significant for understanding the connection between industrial robot adoption and green development at the urban level and for exploring pathways for green transformation. [ABSTRACT FROM AUTHOR]

Defensin-like proteins are conserved in multicellular organisms and contribute to innate immune responses against fungal pathogens. In rice, defensins play a novel role in regulating cadmium (Cd) efflux from the cytosol. However, whether the antifungal activity of defensins correlates with Cd-efflux function remains unknown. In this study, we isolated an endophytic Fusarium , designed Fo 10, by a comparative microbiome analysis of rice plants grown in a paddy contaminated with Cd. Fo 10 is tolerant to high levels of Cd, but is sensitive to the defensin-like protein OsCAL1, which mediates Cd efflux to the apoplast. We found that Fo 10 symbiosis in rice is regulated by OsCAL1 dynamics, and Fo 10 coordinates multiple plant processes, including Cd uptake, vacuolar sequestration, efflux to the environment, and formation of Fe plaques in the rhizosphere. These processes are dependent on the salicylic acid signaling pathway to keep Cd levels low in the cytosol of rice cells and to decrease Cd levels in rice grains without any yield penalty. Fo 10 also plays a role in Cd tolerance in the poaceous crop maize and wheat, but has no observed effects in the eudicot plants Arabidopsis and tomato. Taken together, these findings provide insights into the mechanistic basis underlying how a fungal endophyte and host plant interact to control Cd accumulation in host plants by adapting defense responses to promote the establishment of a symbiosis that permits adaptation to high-Cd environments. This study identifies an endophytic Fusarium Fo 10 that interacts reciprocally with the defensin-like protein OsCAL1 to reduce cytosolic Cd levels in rice. Fo10 modulates iron plaque formation, vacuolar Cd sequestration, and rhizosphere Cd efflux likely by activating SA signaling pathway. [ABSTRACT FROM AUTHOR]

Understory vegetation plays a crucial role in mediating the natural development of forest ecosystems. The removal of understory vegetation, as a common forest management practice, may have a significant impact on soil properties. However, a global perspective on how understory removal might affect soil biogeochemical properties is still lacking. To fill this knowledge gap, we performed a meta-analysis with 2059 observations collected from 71 peer reviewed publications to evaluate the effects of understory vegetation removal on soil carbon (C), nitrogen (N), phosphorus (P), potassium (K), and microbial biomass. We found that (1) removal of the understory significantly increased soil nitrates (NO 3 −) concentration by 6.5 %, but decreased the stocks of C and N, the concentrations of N, available K (AK) and microbial biomass C (MBC), and fine root biomass by 19.4, 15.1, 7.9, 19.9, 13.5 and 32.2%, respectively; (2) mycorrhizal association significantly mediated understory removal effects on soil organic C (SOC) and dissolved organic C (DOC) concentrations, and soil pH, while canopy type had a significant impact on the effects of understory removal on soil K, AK, NO 3 −, MBC concentrations, C:N ratio, and soil pH; (3) soil depth had a negative impact on the effects of understory removal on SOC, AK, ammonium nitrogen (NH 4 +) concentrations, and soil moisture; and (4) mycorrhizal association, soil depth, slope, forest stand age, elevation, and MAT were the most important moderator variables. Our results suggest that the removal of understory vegetation generally have negative effects on soil biogeochemical properties, and that managing understory vegetation is important for promoting the healthy development of forest ecosystems. [ABSTRACT FROM AUTHOR]