Investigating the distribution of microplastics in soils from e-waste dismantling sites and their adsorption of heavy metals.

Microplastics are characterized by strong hydrophobicity, large specific surface area. In addition to the pollutant they contain, the heavy metals adsorbed on the surface of microplastics can migrate or be transformed with them into the environmental medium, which is potentially harmful to humans. The distribution characteristics of microplastics in contaminated soil at the e-waste dismantling site were studied. The study investigated the adsorption characteristics of polyvinyl chloride (PVC), polypropylene (PP) and acrylonitrile-butadiene-styrene (ABS) on copper (Cu), zinc (Zn) and lead (Pb). It analysed the influence of various factors on the adsorption process of heavy metals, the adsorption law of microplastics on some of the heavy metals in the environment, and the risk of heavy metal release from microplastics to soil. The results showed that ABS and PP were the main microplastics in the contaminated soil. Among them, black, white and transparent microplastics accounted for 89.91%. The shape of microplastics is mainly granular, and microplastics with a particle size of 1-2 mm accounted for the largest proportion. Further studies showed that plastic particles made of ABS, PP and PVC also have the adsorption capacity for different types of heavy metals in soil, and the trends of adsorption capacity are: PP>PVC>ABS. When PP does not reach adsorption equilibrium in the adsorption process, the smaller the particle size and the more added amount, the greater the adsorption capacity. This is because the smaller the particle size of the microplastic is, the more adsorption points it can provide, increasing its ability to adsorb heavy metal ions.

Validation of Luminex immunological and competitive Luminex immunological assays for clinical immunogenicity assessment of a 14-valent recombinant human papillomavirus vaccine.

A novel virus-like particle (VLP)-based multivalent recombinant human papillomavirus (HPV) vaccine was developed and evaluated in human, including 14 HPV-type specific VLP antigens (HPV6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59). The pseudovirus-based neutralizing assay (PBNA) method is widely used for immunogenicity assessment of HPV vaccine in clinical trials. However, as many as 14 antigen-specific antibody levels need be determined, PBNA is, for many reasons, challenging and time-consuming. In this study, we developed a Luminex immunological assay (LIA) and a competitive Luminex immunological assay (cLIA). These methods increase the throughput, reproducibility and precision, as well as reduce the complexity. All assay parameters showed good characteristics in the validation of both methods, benefiting from highly purified and structurally correct VLPs, high specific antibodies, standard VLP-microspheres and PE-mAbs conjugating process, adequate assay development and stable system. Validation data support the use of both methods for immunogenicity assessment in clinical trials. LIA showed higher sensitivity than cLIA, and due to limited epitopes of mAb, cLIA detected lower antibody responses, and therefore, fewer antibodies. This work not only supports clinical trials of 14-valent HPV vaccines more efficiently and reliably, but also provides a set of validation strategies and usable standards for general vaccine immunogenicity testing.

Immobilization of heavy metals in biochar by co-pyrolysis of sludge and CaSiO3.

Sludge pyrolysis has become an important method of sludge recycling. Stabilizing heavy metals in sludge is key to sludge recycling. Currently, research on the co-pyrolysis of sludge and industrial waste is limited. This study aims to explore the impact and mechanism of the co-pyrolysis of sludge and CaSiO3 (the main component of slag) and to achieve the concept of "treating waste with waste". To this end, we added different proportions of CaSiO3 (0%, 3%, 6%, 9%, 12%, and 15%) for the co-pyrolysis with sludge, and varied the pyrolysis temperatures (300, 400, 500, 600, and 700 °C) and retention times (15, 30, 60, and 120 min) to study heavy-metal stabilization in sludge. Consequently, the optimum dosage of CaSiO3 required for the immobilization of different heavy metals was 9% (Cu, Zn, Pb, and Cr) and 15% (Ni). The contents of Cu, Zn, Pb, Cr, and Ni in the stable state (oxidized and residual states) were 92.73%, 79.23%, 99.55%, 92.43% and 90.33% respectively. At a pyrolysis temperature of 700 °C, the steady-state proportions of Cr, Pb, and Zn were 88.12%, 90.21%, and 77.21%, respectively. At a pyrolysis temperature of 400 °C, the stable-Cu and -Ni contents were 97.21% and 99.43%, respectively. The optimal dwelling time was 15 min. The results showed that the CaSiO3 addition weakened the O-H stretching vibration peak intensity, promoted the formation of aromatic and epoxy ring structures, and enhanced the heavy-metal immobilization. Furthermore, the CaSiO3 decomposition during co-pyrolysis produced SiO2, CaO, and Ca(OH)2, which helped stabilize heavy metals.

Indoor air particles in research vessel from Shanghai to Antarctic: Characteristics, influencing factors, and potential controlling pathway.

Despite millions of seafarers and passengers staying on ships each year, few studies have been conducted on the indoor air quality inside ship hulls. In this study, we investigated the levels and size distribution of indoor particulate matter during two cruises of the research vessel "Xuelong" from Shanghai to Antarctica. The results showed that the particle size less than 2.5 µm (PM2.5), and particle size less than 10 µm (PM10) concentrations in different rooms of the ship widely varied. We observed high particulate matter (PM) levels in some of the rooms. The mass concentration distribution was dominated by 1-4 µm particles, which may have been caused by the hygroscopic growth of fine particles. The dominant factors influencing PM concentrations were indoor temperature, relative humidity, and human activity. We quantified contributions of these factors to the levels of indoor particles using a generalized additive model. In clean rooms, the levels of indoor particles were controlled by temperature and relative humidity, whereas in polluted rooms, the levels of indoor particles were mainly influenced by temperature and human activity, which implied that controlling temperature and human activity would efficiently reduce the levels of indoor particles.

Co-pyrolysis of sewage sludge and Ca(H2PO4)2: heavy metal stabilization, mechanism, and toxic leaching.

The presence of unstable heavy metals in sewage sludge (SS) restricts its resource utilization. In this study, Ca(H2PO4)2 and SS were co-pyrolyzed to produce biochar, which contained relatively stable heavy metals. X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, and inductively coupled plasma atomic emission techniques were used to analyze the physical and chemical properties and heavy metal content of the biochar. The results indicated that co-pyrolysis of SS with Ca(H2PO4)2 resulted in the production of more stable heavy metals in the SS. The optimal co-pyrolysis conditions were a blended ratio of 15% Ca(H2PO4)2, 650 °C final temperature, 15 °C min-1, and 60 min retention time. The potential stabilization mechanisms of heavy metals were as follows: (1) organic decomposition and moisture (sourced from Ca(H2PO4)2 decomposition) evaporation resulted in greater biochar surface porosity; (2) phosphorous substances were complexed with heavy metals to form metal phosphates; and (3) the mixture reactions among inorganic substances, pyrolysis products of organics, and heavy metals resulted in the formation of highly aromatic metallic compounds. Additionally, the potential environmental risks posed by the heavy metals decreased from 65.73 (in SS) to 4.39 (in biochar derived from co-pyrolysis of SS and 15% of Ca(H2PO4)2). This study reports on a good approach for the disposal of SS and the reduction of its environmental risk.

Co-pyrolysis of monobasic potassium phosphate and plastic processing sludge: Characteristics and environmental risks of potentially toxic elements.

A high concentration of potentially toxic elements (PTEs) can be frequently observed in the plastic processing sludge (PPS), thereby restricting its environmental applications. The main objective of this study was to investigate the effects of the co-pyrolysis of PPS and KH2PO4 (0, 5, 10 and 20 wt%) on the characteristics and environmental risks associated with the PTEs in PPS and derived chars. General characteristic analysis revealed that the char yield, ash content, pH, and particle size of the chars prepared with KH2PO4 were greater than those of the char prepared without KH2PO4 by 3.13-4.89 wt%, 2.95-4.4 wt%, 0.77-0.93, and 9.64-30.07 µm, respectively. The results of sequential extraction indicated that co-pyrolysis with KH2PO4 could considerably increase the distribution of PTEs in the F4 fraction (non-bioavailable) in PPS by 1.30-65.90% when compared with that obtained via co-pyrolysis with 5 wt% of KH2PO4. The toxic leaching tests indicated that the leaching concentrations of Cr, Ni, Cu, Zn, Cd, and Pb in the char prepared without KH2PO4 decreased to different extents when PPS was subjected to co-pyrolysis with KH2PO4, especially in case of co-pyrolysis with 5 wt% of KH2PO4. The range of decrease was 26.40-88.34%. However, in case of Cu, Zn, and Pb, the leaching concentration of the chars prepared with more than 10 wt% of KH2PO4 increased owing to the decomposition of (Cu Zn)PbVO4(OH) in an acidic environment. The results obtained using Hakanson's equations revealed that the potential ecological risk associated with the PTEs in chars obtained by co-pyrolysis with KH2PO4 decreased, with a minimum decrease of 38.17%. In addition, the risk level associated with PPS reduced from considerable to low after co-pyrolysis with KH2PO4. The observations of this study imply that the co-pyrolysis of PPS with KH2PO4 can be a promising treatment for PTE immobilization.

Confining Tiny MoO2 Clusters into Reduced Graphene Oxide for Highly Efficient Low Frequency Microwave Absorption.

Herein, a supermolecular-scale cage-confinement pyrolysis strategy is proposed to build two dielectric electromagnetic wave absorbents, in which MoO2 nanoparticles are sandwiched uniformly between porous carbon shells and reduced graphene oxide (RGO). Both sandwich structures are derived from hybrid hydrogels doped by two different crosslinkers (with/without oxygen bridge), which can precisely confine Mo source (e.g., PMo12 ). Without adding magnetic components, both absorbents exhibit excellent low frequency absorption performance in combination with electrically tunable ability and enhanced reflection loss value, which is superior over other relative 2D dielectric absorbers and satisfies the requirements of portable electronics. Notably, introducing oxygen bridges in the crosslinker generates a more stable confining configuration, which in turn renders its corresponding derivative exhibiting an extra multifrequency electromagnetic wave absorption trait. The intrinsic electromagnetic wave adjustment mechanism of the ternary hybrid absorbent is also explored. The result reveals that the elevated electromagnetic wave absorbing property is attributed to moderate attenuation constant and glorious impendence matching. The cage-confinement pyrolysis route to fabricate 2D MoO2 -based dielectric electromagnetic wave absorbents opens a new path for the design of electromagnetic wave absorbents used in multi/low frequency.

Migration characteristics of heavy metals during simulated use of secondary products made from recycled e-waste plastic.

Recycling of plastics from e-waste can conserve resources, however, aging during the use of plastic products can cause the migration of heavy metals in additives. This study presents a methodology for evaluating the risks of heavy metals in waste plastic secondary products during long term use associated with heavy metal migration. The study processes were investigated by: (1) recycling waste plastics and producing secondary products; (2) thermal aging of secondary products; and (3) toxic leaching used to quantitatively analyse the dissolution of heavy metals. Combined with the changes in mechanical properties and microstructure, the effect of aging on the migration of heavy metals was observed. The results showed that the polymer appeared to delaminate, the adhesion of waste plastics to additives decreased, and the mechanical properties clearly decreased after the thermal aging experiment. Leaching experiments showed that the leached concentrations of Ni, Cu, Zn, Pb, and Sb in the three types waste plastic products increased over time. After 8 d of aging, the leached concentrations of Ni, Sb, and Pb exceeded the third, fourth, and third class of the groundwater quality standard, respectively. Specifically, the concentrations of Sb were 141, 289, and 21.1 times higher than the maximum permissible level. Therefore, management hierarchy and safe environmental recycling methods should be developed to reduce the risk of heavy metals in waste plastic secondary products.

Integrating carbonyl iron with sponge to enable lightweight and dual-frequency absorption.

In this work, sponge impregnated with iron pentacarbonyl was utilized to obtain a novel composite in which the carbonyl iron (CI) was embedded in a graphitized carbon matrix (CI-C). The CI that results from the thermal pyrolysis of iron pentacarbonyl can homogeneously disperse into the pore structures of the sponge skeleton, which not only improves the stability of the CI, but also modifies the impedance matching character. Moreover, the sponge bulk turns into graphitized carbon during the heat treatment (graphitized catalysis of magnetic metal on carbon at high temperature). Due to the respective strong dissipation ability of CI and the graphitized carbon matrix, the as-prepared CI-C sample exhibits a good microwave absorption performance, including expanding the effective absorption bandwidth and reduced weight, compared to pure CI. Moreover, the sample with 30 wt% paraffin loading not only shows strong reflection loss absorbing ability, but also possesses continuous dual-absorption peaks (9.96 GHz, -38.7 dB, and 13.8 GHz is -37.6 dB). This work not only extends the application of carbonyl iron as a lightweight microwave absorber with dual-absorption peaks but also initiates a new approach for artificially designed carbon-based composites via a simple sponge-impregnation method.

Pollution analysis of soil polycyclic aromatic hydrocarbons from informal electronic waste dismantling areas in Xinqiao, China.

Polycyclic aromatic hydrocarbons (PAHs) are considered to be persistent organic pollutants, which pose a great threat to human health and the surrounding environment. In order to explore the influence of informal electronic waste (e-waste) dismantling activities on inhabitants who live nearby, soil samples were collected from informal e-waste dismantling areas in Xinqiao, China and analysed for 16 United States Environmental Protection Agency (USEPA) priority PAHs. Results indicated that the 16 USEPA priority PAHs were found at all seven sampling locations. Sampling location 3, which was only 10 m away from a residential area, had 1053.69 µg kg-1 of PAHs and seriously exceeded the standard value specified by the Netherlands. The total percents of 4-ring and 5-ring PAHs accounted for 61.74 and 71.70%, respectively, indicating that most of the detected PAHs belonged to high-ring PAHs. The informal e-waste dismantling activities are the major sources of soil PAHs in Xinqiao. Furthermore, the concentration of seven carcinogenic PAHs was 114.76 µg kg-1 and represented a potential health risk to humans. Thereinto, benzo[a]pyrene contributed the most, accounting for more than 50% in these locations. Our results may provide a reference about the influence of informal e-waste dismantling activities on the surrounding inhabitants and suggest that e-waste dismantling activities must be conducted in a formal enterprise which is far away from residential areas.

Heavy metals in soil at a waste electrical and electronic equipment processing area in China.

For the objective of evaluating the contamination degree of heavy metals and analysing its variation trend in soil at a waste electrical and electronic equipment processing area in Shanghai, China, evaluation methods, which include single factor index method, geo-accumulation index method, comprehensive pollution index method, and potential ecological risk index method, were adopted in this study. The results revealed that the soil at a waste electrical and electronic equipment processing area was polluted by arsenic, cadmium, copper, lead, zinc, and chromium. It also demonstrated that the concentrations of heavy metals were increased over time. Exceptionally, the average value of the metalloid (arsenic) was 73.31 mg kg-1 in 2014, while it was 58.31 mg kg-1 in the first half of 2015, and it was 2.93 times and 2.33 times higher than that of the Chinese Environmental Quality Standard for Soil in 2014 and the first half of 2015, respectively. The sequences of the contamination degree of heavy metals in 2014 and the first half of 2015 were cadmium > lead > copper > chromium > zinc and cadmium > lead > chromium > zinc > copper. From the analysis of the potential ecological risk index method, arsenic and cadmium had higher ecological risk than other heavy metals. The integrated ecological risk index of heavy metals (cadmium, copper, lead, zinc, and chromium) and metalloid (arsenic) was 394.10 in 2014, while it was 656.16 in the first half of 2015, thus documenting a strong ecological risk.

Application of thermally treated sludge residues on an e-waste contaminated soil: effects on PTE bioavailability, soil physicochemical and biological properties, and L. perenne growth.

In the context of sustainable development, potentially toxic element (PTE) contamination of soil and large-scale disposal of sludge are two major environmental issues that need to be addressed urgently. It is of great significance to develop efficient and green technologies to solve these problems simultaneously. This study investigated the effects of a 5% addition of thermally treated sludge residues (fermentation and pyrolysis residues) in synergy with L. perenne on soil organic matter, mineral nutrients, PTE speciation, and PTE uptake and transport by L. perenne in an e-waste-contaminated soil through pot experiments. The results showed that the thermally treated sludge residues significantly increased soil electrical conductivity, cation exchange capacity, organic matter, available phosphorus, and exchangeable potassium contents. New PTE-containing crystalline phases were detected, and dissolved humic substances were found. Sludge fermentation residue significantly increased dissolved organic matter content, whereas sludge pyrolysis residue showed no significant effect. The combination of thermally treated sludge residues and L. perenne increased the residual fractions of Cu, Zn, Pb, and Cd. The thermally treated sludge residues promoted L. perenne growth, increasing fresh weight, plant height, and phosphorus and potassium uptake. The uptake of Cu, Zn, Pb, and Cd by L. perenne was significantly reduced. This approach has the potential for applications in the ecological restoration of e-waste-contaminated soils.

Carding Behavior and Bearing Capacity of a Newly Developed Cylinder Card-Clothing Compatible with Cotton and Terylene Fibers by Nb Alloying of AISI 1090 Steel.

Changing the metallic card clothing on a carding machine is costly when the spinning mills want to card different fibers from cotton to terylene or vice versa. This article proposes a newly developed cylinder card clothing compatible with cotton and terylene fibers by Nb alloying of AISI 1090 steel so that the spinning mills can change the type of fiber without changing the card clothing. Based on an idea developed from classical carding balance theory to study the adaptability of the cylinder card clothing for cotton and terylene fibers, the wall shear stress was used as the basis for compatibility analysis of carding behavior and bearing capacity with cotton and terylene fibers and as the focus of this study. Nb alloying of AISI 1090 steel showed good wear resistance in carding areas after heat treatment with high hardness above 840 Hv0.2 and extremely fine grain grade of 13.5 class, which increased about 25% compared to conventional 80 WV. The testing results in the spinning mills, including one cotton and two terylene fibers, showed good performance with this newly developed card clothing. In conclusion, the card clothing made of Nb alloying of AISI 1090 steel can handle different fibers with acceptable carding performance.

[Microorganisms used for bioleaching of metals from typical solid wastes and their leaching mechanism: a review].

Typical solid wastes contain many metal resources, which are worthy of recycling. The bioleaching of typical solid waste is affected by multiple factors. Green and efficient recovery of metals based on the characterization of leaching microorganisms and the elucidation of leaching mechanisms may contribute to the implementation of China's "dual carbon" strategic goals. This paper reviews various types of microorganisms used for leaching metals from typical solid wastes, analyzes the action mechanism of metallurgical microorganisms, and prospects the application of metallurgical microorganisms to facilitate the application of metallurgical microorganisms in typical solid wastes.

Fate and health risk assessment of heavy metals in Brassica chinensis L. (pak-choi) and soil amended by sludge-based biochar.

Biochar is widely used in agriculture to efficiently solve the problem of sludge. In this study, sludge-based biochar (referred to as BC1, BC2, and BC3) was prepared by mixing sludge with FeCl3, Na2SiO3, and Ca (H2PO4)2, respectively. Then, it was mixed with fresh soil to plant Brassica chinensis L. The analysis of the effects of the three biochar types showed that all of them were beneficial to the growth of Brassica chinensis L. We added the biochar to the soil and found that the concentration of heavy metals did not exceed the recommended threshold. Additionally, the aboveground part of Brassica chinensis L. met the standard requirement for food safety (GB 2761-2017). Notably, BC3 stood out with the best effect on the growth of Brassica chinensis L. and resulted in the improvement of the physical and chemical properties of soil such as ammonium nitrogen, available phosphorus, and available potassium (BC3 was followed by BC2 and BC1). BC3 could efficiently inhibit the migration of heavy metals, thereby reducing the overall heavy metal pollution level and ameliorating the soil nutrients. BC3 could increase the organic carbon by 258.92%, available phosphorus by 234.45%, and available potassium by 37.12% compared with the CK group. The THQ and TTHQ estimates of Brassica chinensis L. were lower than one, indicating that the health risk of heavy metal intake was not prominent. Additionally, the application of the proposed biochar could reduce the form of F1 (acid extracted state) and increase the form of F4 (residue state) in soil. Overall, we conclude that the application of the proposed biochar can promote the root absorption of heavy metals and inhibit the migration of heavy metals.

Mechanism and application of modified bioelectrochemical system anodes made of carbon nanomaterial for the removal of heavy metals from soil.

Bioelectrochemical techniques are quick, efficient, and sustainable alternatives for treating heavy metal soils. The use of carbon nanomaterials in combination with electroactive microorganisms can create a conductive network that mediates long-distance electron transfer in an electrode system, thereby resolving the issue of low electron transfer efficiency in soil remediation. As a multifunctional soil heavy metal remediation technology, its application in organic remediation has matured, and numerous studies have demonstrated its potential for soil heavy metal remediation. This is a ground-breaking method for remediating soils polluted with high concentrations of heavy metals using soil microbial electrochemistry. This review summarizes the use of bioelectrochemical systems with modified anode materials for the remediation of soils with high heavy metal concentrations by discussing the mass-transfer mechanism of electrochemically active microorganisms in bioelectrochemical systems, focusing on the suitability of carbon nanomaterials and acidophilic bacteria. Finally, we discuss the emerging limitations of bioelectrochemical systems, and future research efforts to improve their performance and facilitate practical applications. The mass-transfer mechanism of electrochemically active microorganisms in bioelectrochemical systems emphasizes the suitability of carbon nanomaterials and acidophilic bacteria for remediating soils polluted with high concentrations of heavy metals. We conclude by discussing present and future research initiatives for bioelectrochemical systems to enhance their performance and facilitate practical applications. As a result, this study can close any gaps in the development of bioelectrochemical systems and guide their practical application in remediating heavy-metal-contaminated soils.

Separation and recycling of Au and Ag from waste light-emitting diodes.

Waste light-emitting diodes (LEDs) contain rare and precious metals which have attracted wide attention due to their high resource. In this study, experimental research was conducted on the separation and recycling of Au and Ag from LEDs. Firstly, thermal treatment and sieving were done to separate and enrich the metals in LEDs. With the constant heating rate of 10°C/min to 450°C under air atmosphere, the metals could be effectively separated from organics and the rare metals Au and Ag mainly concentrate in particles with a diameter ≤600 µm, whose concentration is about 1816 and 1429 mg/kg, respectively. Then, a mix-acid system of HCl-CH3COOH was introduced to leach Au and Ag from the enriched sample. The results show that the HCl-CH3COOH system could effectively leach Au and Ag, and the leaching performance of Au and Ag can reach 95.4% and 96.2%, respectively under the recommended conditions (total acid concentration 5 mol/L, HCl:CH3COOH = 4:1, leaching temperature 80°C, solid-liquid ratio 1:100, leaching time 5 h). The study can provide a new option for recycling of waste LEDs, which also provide a more environment-friendly method for Au and Ag leaching from industrial wastes.

Spatiotemporal distribution and influencing factors of secondary organic aerosols in the summer atmosphere from the Bering Sea to the western North Pacific.

To better understand the formation process of biogenic and anthropogenic secondary organic aerosols (BSOA and ASOA) in the marine atmosphere under the background of global warming, aerosol samples were collected over three summers (i.e., 2014, 2016 and 2018) from the Bering Sea (BS) to the western North Pacific (WNP). The results showed that temporally, atmospheric concentrations of isoprene-derived SOA (SOAI) tracers were the lowest in 2014 regardless of the marine region, while atmospheric concentrations of monoterpenes-derived SOA (SOAM) tracers in this year were the highest and the aerosols were more aged than those in the other two years. In comparison, the concentrations of ß-caryophyllene-derived and toluene-derived SOA (SOAC and SOAA) tracers were relatively low overall. Spatially, the concentrations of SOA tracers were significantly higher over the WNP than over the BS, with SOA tracers over the BS mainly coming from marine sources, while the WNP was strongly influenced by terrestrial inputs. In particular, for land-influenced samples from the WNP, NOx-channel products of SOAI were more dependent on O3 and SO2 relative to HO2-channel product, and the high atmospheric oxidation capacity and SO2 could promote the formation of later-generation SOAM products. The extent of terrestrial influence was further quantified using a principal component analysis (PCA)-generalized additive model (GAM), which showed that terrestrial emissions explained more than half of the BSOA tracers' concentrations and contributed almost all of the ASOA tracer. In addition, the assessment of secondary organic carbon (SOC) highlighted the key role of anthropogenic activities in organic carbon levels in offshore areas. Our study revealed significant contributions of terrestrial natural and anthropogenic sources to different SOA over the WNP, and these relevant findings help improve knowledge about SOA in the marine atmosphere.

Electrochemical oxidation of copper-clad laminate for manufacturing printed circuit boards via bioleaching by the fungus Phanerochaete chrysosporium.

The leaching and electrochemical oxidation of the copper-clad laminate for manufacturing printed circuit boards were investigated in systems with and without the fungus P. chrysosporium, which yielded the copper-leaching efficiencies of 54% and 7.0%, respectively. In particular, the formation of a biofilm on the electrode surface reduced the open-circuit potential and increased the corrosion level, and the degree of increase and the rate of change of the current density in the fungal leaching system were higher than those of the sterile system. In addition, the cyclic voltammetry curves showed oxidation peaks that correspond to the oxidation of Cu to Cu2+. Further, for the fungal leaching system, the peak potential was highly negative and the curve area and peak current density were relatively high. Moreover, the electrochemical polarization parameters and the impedance characteristics were affected by the fungus, and the leaching systems were controlled by charge transfer and diffusion. In summary, P. chrysosporium can accelerate the leaching of copper as a result of the formation of extracellular electron transfer-induced microbiologically influenced corrosion (EET-MIC) and metabolite-induced microbiologically influenced corrosion (M-MIC). The enzymes and organic acids, which act as fungal metabolites, participate in the leaching of copper.

A breathable and flexible fiber cloth based on cellulose/polyaniline cellular membrane for microwave shielding and absorbing applications.

High-performance electromagnetic (EM) wave absorption and shielding materials integrating with flexibility, air permeability, and anti-fatigue characteristics are of great potential in portable and wearable electronics. These materials usually prepared by depositing metal or alloy coatings on fabrics. However, the shortcomings of heavy weight and easy corrosion hamper its application. In this work, the cellulose nanofiber (CF) fabric was prepared by electrospinning technology. Then, conductive polyaniline (PANI) was deposited on the CF surface via a facile in-situ polymerization process. The interweaving cellulose/polyaniline nanofiber (CPF) composite constructs a conductive network, and the electrical conductivity can be adjusted by polymerization time. Benefiting from optimal impedance matching, strong conductive loss, as well as interfacial polarization, the CPF possesses excellent EM absorption performance. The minimum reflection loss (RLmin) value is -49.24 dB, and the effective absorption bandwidth (RL < -10 dB, fe) reaches 6.90 GHz. Furthermore, the CPF also exhibits outstanding electromagnetic interference (EMI) shielding capability with shielding efficiency (SE) of 34.93 dB in the whole X band. Most importantly, the lightweight CPF fabrics have the merits of mechanical flexibility, breathability and wash resistance, which is highly applicable for wearable devices.