Residual Form Research Articles

Effect of sludge-based biochar on the stabilization of Cd in soil: experimental and theoretical studies

Soil heavy metal contamination and sludge disposal have become globally environmental issues problems of great concern. Utilizing sludge pyrolysis to produce biochar for remediating heavy metal-contaminated soil is an effective strategy to solve these two environmental problems. In this study, municipal sewage sludge and papermaking sludge were used as feedstock to prepare co-pyrolyzed biochar, which was then applied to reduce the toxicity of Cd in soil. The results indicated that the application of co-pyrolyzed biochar significantly increased soil pH, CEC, and enzyme activity, while decreasing the content of available Cd in the soil. Following the application of 3% co-pyrolyzed biochar, the proportion of acid-soluble Cd in the soil decreased to below 46%, as the biochar facilitated the conversion of leachable acid-soluble Cd to stable oxidizable and residual forms through precipitation and complexation. The DFT computational results indicate that the aromatics in co-pyrolyzed biochar can adsorb Cd ions through cation-π interactions, while carboxyl, hydroxyl, aldehyde, and amide groups can provide more electrons for the adsorption of Cd ions, resulting in stronger adsorption capacities. The study findings provide a feasible solution for the resourceful treatment of sludge and the remediation of heavy metal-contaminated soil.

Bioremediation of Heavy Metal-Contaminated Solution and Aged Refuse by Microbially Induced Calcium Carbonate Precipitation: Further Insights into Sporosarcina pasteurii.

Recently, the ability of microbial-induced calcium carbonate precipitation (MICP) to remediate heavy metals has been widely explored. Sporosarcina pasteurii was selected to remediate heavy metal-contaminated solution and aged refuse, exploring the feasibility of Sporosarcina pasteurii bioremediation of heavy metals and analyzing the changes in heavy metal forms before and after bioremediation, as well as the mechanism of remediation. The results showed that Sporosarcina pasteurii achieved remediation rates of 95%, 84%, 97%, and 98% for Cd, Pb, Zn, and Cr (III) in contaminated solution, respectively. It also achieved remediation rates of 74%, 84%, and 62% for exchangeable Cd, Pb, and Zn in aged refuse, respectively. The content of exchangeable Cr (III) before bioremediation was almost zero. The content of heavy metals with exchangeable form and carbonate-bounded form in aged refuse decreased after bioremediation, while the content of heavy metals with iron-manganese oxide binding form and residual form increased. Simultaneously, the presence of Fe and Al components in aged refuse, as well as the precipitation of calcium carbonate produced during the MICP process, jointly promotes the transformation of heavy metals into more stable forms.

Neuromorphological Effects of Acute and Chronic Electromagnetic Irradiation

Morphological changes in the cerebral cortex were studied in model experiments on three types of laboratory animals (mice, rats, dogs) exposed to both acute and chronic electromagnetic radiation. It has been established that neurons are highly reactive and at the same time plasticity to the electromagnetic factor. Changes in neurons are more pronounced with general than with partial irradiation. The greatest response was found from the structures of the protein-synthesizing system of neurons, as well as their interneuronal contacts. After 3 days of the recovery period, changes were detected only at the ultrastructural level in the form of residues, decayed organelles, clusters of lysosomes and local foci of brain edema. With chronic exposure to microwaves with exposure at the “zero effect” level, the sensitivity of neurons to electromagnetic radiation was characterized by species differences and was inversely dependent on the animal’s body weight: mice were the most sensitive, the structures of the rat nervous system were more resistant, and the nervous structures of dogs had the least sensitivity.

Nitrogen, sulfur, iron, and microbial communities co-shape the seasonal biogeochemical behaviors of As and Sb in coastal tidal flat wetlands associated with rivers

Arsenic (As) and antimony (Sb) are affected by complex biogeochemical processes in coastal ecosystems. However, the influence of N, S, Fe, and microbial communities on the biogeochemistry of As and Sb in coastal tidal flat wetlands remain uncertain, particularly when rivers flow into these areas. This study combined diffusive gradients in the thin-film technique with high-throughput sequencing to investigate the release and vertical distribution of As and Sb in river and coastal tidal flat wetland sediments. The results indicated a distinct stratification phenomenon in the As release at depths ranging from 20 mm to −150 mm. At river sites, the release of As occurred in the upper layer (above −40 mm), with peak values of 4.3 and 9.3 μg/L at HS and SY sites in summer, respectively, likely due to anaerobic ammonium oxidation. In the lower layer (below −40 mm), both As and Sb were released, and this was possibly due to Fe reduction. However, at the coastal tidal flat sites, the release of As and Sb may have been driven by anaerobic ammonium oxidation, dissimilatory nitrate reduction to ammonium, sulfate reduction, and Fe reduction. At the river sites, As exhibited increased activity during the summer, and the residual forms were converted more easily into mobile forms. Sb remained relatively stable during both winter and summer. Conversely, both As and Sb primarily existed in residual forms and exhibited higher stability during summer in the coastal tidal flat sites. The microbial phyla Nitrospirota (3.6−7.0 %) and Acidobacteriota (9.5−10.2 %) were more prevalent at the river sites, whereas Desulfobacterota (8.8−12.0 %) and Firmicutes (0.13−27.9 %) were more prevalent at the coastal tidal flat sites. The bacterial genera involved in the N, S, and Fe transformation processes differed between the two sites, and they were primarily Thiobacillus, Limnobacter, and Sulfurovum at the river sites and Sva1033, Anaeromyxobacter, and Sva0485 at the coastal tidal flat sites. In this study, the microorganisms that mediated N, S, and Fe complex processes at various depths in the sediment–water interface were decoupled to elucidate the effect of these processes on the biogeochemical behavior of As and Sb as they move from rivers to coastal tidal flat wetlands.

Parametric Quantile Autoregressive Conditional Duration Models With Application to Intraday Value‐at‐Risk Forecasting

ABSTRACTThe modeling of high‐frequency data that qualify financial asset transactions has been an area of relevant interest among statisticians and econometricians—above all, the analysis of time series of financial durations. Autoregressive conditional duration (ACD) models have been the main tool for modeling financial transaction data, where duration is usually defined as the time interval between two successive events. These models are usually specified in terms of a time‐varying mean (or median) conditional duration. In this paper, a new extension of ACD models is proposed which is built on the basis of log‐symmetric distributions reparametrized by their quantile. The proposed quantile log‐symmetric conditional duration autoregressive model allows us to model different percentiles instead of the traditionally used conditional mean (or median) duration. We carry out an in‐depth study of theoretical properties and practical issues, such as parameter estimation using maximum likelihood method and diagnostic analysis based on residuals. A detailed Monte Carlo simulation study is also carried out to evaluate the performance of the proposed models and estimation method in retrieving the true parameter values as well as to evaluate a form of residuals. Finally, we derive a semiparametric intraday value‐at‐risk (IVaR) model and then the proposed models are applied to two price duration data sets.

Navigating Pesticide Residue Accumulation in Arable Soils: Insights for Sustainable Agriculture

Adoption and application of wide range chemicals as pesticides for shielding crop against undesirable weeds, insects and pests has increased the overall agricultural productivity in recent decades. According to reports, pesticides which are exposed to a variety of environmental circumstances over an extended period of time cause many of their derivatives to survive in the environment. Accumulation of these chemicals in ecosystems lead their absorption in non-target creatures, planted crops and arable soils, and therefore, causing serious detrimental environmental hazards and many concerns have been brought to light on a worldwide scale. In fact, there may still be health hazards for people associated with the food chain transportation of these pesticide residual compounds. Pesticide residues absorption, on the other hand, is more difficult to understand. Characteristics of the planted crops, the physicochemical qualities of the pesticides and the ambient factors can all have a significant impact on the pesticide residue uptake process and bioavailable concentrations. In the meanwhile, this article will emphasize on overview of these pesticide residue forms and their fate in agricultural soils, mechanisms and factors hindering plant uptake for essential nutrients. To make reasonable risk forecasts for human health, future research must conduct field-based investigations in natural settings.

The oxidation-dissolution behavior of Cr-coated Zr alloy in high temperature water

The corrosion and dissolution behavior of Cr-coated Zr alloy were investigated in high temperature water under varying dissolved oxygen (DO) and temperatures. Results demonstrate that the oxidation and dissolution rates of Cr coatings increase significantly with higher DO levels and temperature, while the Zr substrate remains unaffected by DO concentration. At DO levels below 10 ppb, Cr coatings exhibit high stability, but at 300 ppb DO, rapid corrosion/dissolution and spallation occur. The electrochemical potential (ECP) shifts in response to temperature and DO, driving the dissolution mechanism through three distinct region: steady-state, field-assisted dissolution (FAD), and complete dissolution. During the FAD period, a porous nanocrystalline Cr2O3 layer with residual Cr forms, characterized by non-uniform dissolution due to preferential oxidation at grain boundaries and microstructural defects. The soluble HCrO4− ions form at the base of the porous layer, followed by partial recrystallization at the surface, leading to the development of a thin Cr2O3 crystalline layer.

Alteration of soil microbiomes in an arsenic and antimony co-contamination zone after dam failure

Arsenic (As) and antimony (Sb), two toxic metal(loid)s, behave similarly and commonly occur in mine tailings. Yet, responses of microbes to As and Sb co-contamination in tailings dam failure-affected area remain limited. Herein, soil microbiomes (archaea, bacteria and fungi) across two contrasting sites (tailing-contaminated farmland and nearby undisturbed forestland) at a Sb-Au mining district in Chizhou, China were investigated by high-throughput sequencing. Results showed that As and Sb occurred mainly in the residual form, accounting for 55.82 % and 52.04 %, respectively. The bioavailable form was 12.77 % and 10.39 % in contaminated farmland compared to 13.31 % and 11.66 % in undisturbed forestland, respectively. Contrary to archaea and fungi, bacterial alpha-diversity significantly increased in contaminated farmland. The taxa-taxa interactions in archaea were most robust, followed by bacteria; and fungi were the weakest, which was corresponding to the habitat niche breadth. Microbial communities were affected by the deterministic processes with a modified stochasticity ratio (MST) value of 36.36 %, whereas more stochasticity (MST = 49.71 %) was raised in contaminated farmland than in undisturbed forestland (MST = 36.98 %). The microbial function based on taxonomy-based inference indicated that nitrogen and carbon metabolisms associated with archaea and bacteria increased in contaminated farmland, as well as plant pathogen, wood saprotroph and endophyte related with fungi. The turnover of soil microbiomes was tightly correlated with As and Sb speciation. Collectively, this study reveals that the soil microbial survival strategies to As-Sb co-contamination after dam failure, providing guidance for the development of bioremediation and tailings management strategies.

Refining habitat selection for sulfate-reducing bacteria: Evaluating suitability and adaptability for sulfate-metal wastewater treatment during anaerobic-to-aerobic transitions

Inoculating sulfate-reducing bacteria (SRB) habitats offers an eco-friendly method for treating sulfate-metal laden wastewater, characterized by high sulfate levels, low pH, and elevated heavy metals. This study optimizes source habitat selection of SRB by evaluating groundwater, sewage sludge, and lake sediment, focusing on their suitability and adaptability to aerobic-anaerobic transitions in industrial settings. Sewage sludge, with its slightly acidic pH, reducing environment, and high nutrient levels (Total organic carbon: 207.53 g kg−1, Total nitrogen: 47.12 g kg−1), provides robust SRB potential, as supported by its highest diversity index. However, heavy metals and polycyclic aromatic hydrocarbons pose application challenges. All habitats effectively reduced metal concentrations anaerobically, with Cu removal reaching 95%–99%, and groundwater achieved the highest chemical oxygen demand reduction (63.6%) aerobically. Sludge and sediment showed high biomass and extracellular polymeric substances (EPS) accumulation, while groundwater's nucleic acid-rich EPS enhanced metal immobilization, resulting in stable residual metal forms but with potential remobilization under oxidative conditions. Microbial analysis revealed that Proteobacteria and Firmicutes were key players during transitions, with the highest SRB abundance in groundwater. SRB composition varied across habitats, with Sedimentibacter (13.04%), Desulfovibrio (6.33%), and Desulfomonile (8.1%) dominating in groundwater, sludge, and sediment, respectively, during the anaerobic stage. Functional analysis highlighted sludge's persistence in sulfate reduction under aerobic conditions, while groundwater's limited nitrogen cycle involvement indicated broader biogeochemical limitations. Collectively, these findings highlight strengths and limitations of each habitat as SRB inoculum source, emphasizing the importance of tailored anaerobic-to-aerobic strategies for effective wastewater management.

Fe3O4/Mulberry Stem Biochar as a Potential Amendment for Highly Arsenic-Contaminated Paddy Soil Remediation.

Magnetite-loaded biochar has recently received attention owing to its ability to remove arsenic from contaminated soil. In this study, mulberry stem biochar (MBC) and Fe3O4-loaded mulberry stem biochar (Fe3O4@MBC) were produced and used in a 100-day incubation experiment to investigate their performance in the stabilization of arsenic in paddy soil severely polluted by the As (237.68 mg·kg-1) mechanism. Incubation experiments showed that Fe3O4@MBC was more effective in immobilizing As after incubation for 100 days. Moreover, adding Fe3O4@MBC facilitated the transformation of exchangeable heavy metals into organic-bound and residual forms, thereby reducing As available concentrations, mobility, and bioavailability in the soil, and elevating slightly the soil pH and dissolved organic carbon (DOC). The concentration of TCLP-extractable As (AsTCLP) in contaminated soil was reduced from 93.85 to 7.64 μg·L-1 within 10 d, below the safety limit for drinking water set by the World Health Organization (WHO). The characterization results of Fe3O4@MBC after incubation indicated that the mechanisms for As passivation are linked to redox reactions, complexation, electrostatic attraction, surface adsorption, and coprecipitation. Conclusively, Fe3O4@MBC is a promising amendment in highly As-contaminated soil and provides a theoretical reference in such polluted paddy soil remediation.

Development of polyfunctionalized biochar modified with manganese oxide and sulfur for immobilizing Hg(II) and Pb(II) in water and soil and improving soil health

Mercury (Hg) and lead (Pb) pose significant risks to human health due to their high toxicity and bioaccumulative properties. This study aimed to develop a novel biochar composite (HMB-S), polyfunctionalized with manganese dioxide (α-MnO2) and sulfur functional groups, for the effective immobilization of Hg(II) and Pb(II) from contaminated environments. HMB-S demonstrated superior adsorption capacities of 190.1 mg/g for Hg(II) and 259.9 mg/g for Pb(II), which significantly surpasses the capacities of unmodified biochar (HB) and biochar functionalized solely with Mn (HMB). Mechanistic studies revealed that the immobilization of these metals by HMB-S involved ion exchange, mineral precipitation, surface complexation, and electrostatic interactions. In soil incubation experiments, HMB-S significantly decreased the levels of extractable Hg(II) and Pb(II) compared to the control, reducing the mobility of these metals and converting 17 % of Hg(II) and 26 % of Pb(II) into less bioavailable residual forms. Pot experiments confirmed that all tested biochar materials (HB, HMB, and HMB-S) promoted spinach growth in contaminated soils, with HMB-S being the most effective at lowering Hg(II) and Pb(II) uptake by plants. Additionally, analysis of soil microbial communities indicated that HMB-S altered community composition and increased the relative abundance of metal-resistant bacteria. These findings highlight the potential of polyfunctionalized biochar HMB-S as an effective remediation strategy for Hg and Pb contamination in soil and aqueous environments.

Порівняння ущільнюваності асфальтобетонної суміші із золою-винесення та вапняковим наповнювачем

Introduction. In Ukraine, about 30 % of all electricity is generated from the combustion of solid fuels — coal, shale, peat. In our country, there are about 15 operating thermal power plants that generate about 5 – 6 million tons of ash and slag waste per year as a secondary product. Thus, the fuel and energy complex waste generated in the furnaces of thermal power plants is a huge accumulation of ash in the form of dusty residues and lumpy sludge, as well as various ash and slag mixtures. These products of high-temperature processing (1 200 – 1 700 ºС) of the mineral part of the fuel are widely used in many countries of the world and, given the global trend towards an increase in the share of the secondary market for the use of waste, it is necessary to predict an increase in the rate of their processing in Ukraine. Problem Statement. The road construction industry is one of the strategic industries of Ukraine, and the issue of quality and availability of basic building materials for road construction is particularly acute now, which is directly related to its high material intensity. The known reserves of high-quality raw materials that could be used as asphalt concrete components are constantly decreasing, so it is necessary to look for alternative sources of raw materials for construction materials and explore the possibility of their use. In this regard, the most effective use of local raw materials is the use of industrial waste, which can be one of the solutions to the problem of lack of raw materials of inorganic origin.

An innovative green method for efficient extraction of selenium by melt filtration-vacuum distillation

High-purity selenium is important for technological innovation in fields such as aerospace, military, new energy, and semiconductors, and has become a hot topic in developed countries. Unfortunately, traditional preparation of high-purity selenium faces challenges such as high cost, environmental pollution, and low efficiency. In this study, we introduce an innovative green method that efficiently extracts selenium from crude selenium by combining melt filtration and vacuum distillation. Our approach effectively addresses these challenges. We calculated the potential reactions of the impurities in the selenium melt and analyzed the saturated vapor pressures of various substances. The experimental results showed that volatile impurities such as PbSe and PbTe were largely removed in the form of filter residues during the melt filtration of crude selenium residue at 653 K. The filtered selenium melt was distilled for 120 min at 533 K to obtain refined Se with a total purity of 99.9 %. Through the melt filtration-vacuum distillation process, the removal rates of impurity elements Cu, Pb, As, and Te were 99.35 %, 99.97 %, 99.83 %, and 81.11 %, respectively. Impurity elements were enriched and recovered from the filter and distillation residues. The refined Se was efficiently recovered from crude selenium, and the economic benefits were superior to other processes. This process meets the demands of a clean and efficient selenium metallurgy industry.

Empirical evaluation of the gamma-Pareto regression residuals for influence diagnostics

ABSTRACT For the reliable results of regression analysis, influence diagnostic methods play an important role. The performance of various proposed residuals for the gamma-Pareto regression model (G-PRM) is presented in this study. These proposed residuals are partitioned into standardized and adjusted residual forms. For the detection of influential observations, difference of fits (DFFITS) was used in both standardized and adjusted residuals. To detect influential points, these residuals are compared through Monte Carlo Simulation also real data (Ardennes data) are analysed to show the benefits of the proposed methods. The likelihood residuals performed better for small dispersion than others. Additionally, all forms of adjusted residuals are the same, not much more efficient than the standardized form. All standardized residuals behave in the same way for wider dispersion, and they are superior to the likelihood residuals for the detection of influential points.

B-nZVI optimization of strength and heavy metal stability of lead-contaminated soil solidified by Portland cement.

Traditional cement solidifying or stabilizing heavy metal-contaminated sites often face issues like alkalinity loss, cracking, and poor long-term performance. Therefore, bentonite-supported nano-zero-valent iron (B-nZVI) was introduced to optimize the remediation effect of cement in this paper. The effects of B-nZVI, ordinary Portland cement (OPC), and B-nZVI + OPC on the chemical stability of heavy metals and the physical strength of lead-contaminated soil were compared using semi-dynamic leaching methods, BCR tests, unconfined strength analysis, and micro-assisted analysis. Results demonstrated that the addition of B-nZVI effectively enhanced the remediation efficacy of OPC on lead-contaminated soil. The combination of B-nZVI and OPC exhibited a synergistic repair effect, offering superior physical strength and chemical stability for lead remediation. B-nZVI facilitated the adsorption and enrichment of Pb2+, thereby reducing oxidizable lead and enhancing short-term stabilization. Meanwhile, OPC precipitation and silicate gelling stabilized exchangeable lead into the residual form, necessitating repeated hydration gelling. Additionally, B-nZVI's sealing effect via water absorption delayed the leaching of exchangeable lead, thereby reducing lead migration. Even with only 1% B-nZVI added to the 12% OPC base, the leaching amount of Pb2+ decreased significantly from 67.6 to 6.59mg/kg after 7 d of curing. The unconfined strength of contaminated soil treated with the composite solidifying agent for 7 d was 12.87% higher than that of OPC alone, and for 28 d, it was 36.48% higher. This optimization scheme presents a promising approach for effective and sustainable remediation of heavy metal-contaminated sites.

Adsorption mechanism and remediation of heavy metals from soil amended with hyperthermophilic composting products: Exploration of waste utilization

Due to high humification, hyperthermophilic composting products (HP) show potential for remediating heavy metal pollution. However, the interaction between HP and heavy metals remains unclear. This study investigated the adsorption mechanism and soil remediation effect of HP on heavy metals. The results showed that the maximum adsorption capacity of HP increased by an average of 30.74 % compared to conventional composting products. HP transformed 34.87 % of copper, 42.55 % of zinc, and 35.63 % of lead from exchangeable and reducible forms into residual and oxidizable forms, thus reducing the soil risk level. In conclusion, HP significantly enhanced the adsorption of heavy metals and their transformation from unstable to stable forms, primarily due to the higher content of hydroxyl and carboxyl groups. This study aims to demonstrate the effectiveness of HP for remediating heavy metal pollution and to enhance the understanding of the underlying mechanism, which lays a foundation for waste utilization.

Unlocking the potential of alkalizing bacteria in cadmium remediation: Unveiling mechanisms and efficacy

Vegetables represent a primary pathway for cadmium (Cd) exposure, posing a serious threat to human health. The utilization of alkalizing bacteria presents an effective means to elevate pH, thereby facilitating the alteration of Cd migration efficiency. This study validated the efficacy of alkalizing bacteria Stenotrophomonas sp. H225 (SH225) in promoting plant growth and reducing Cd accumulation in roots and leaves through hydroponic experiments. It further elucidated the specific mechanisms by which SH225 reduces Cd migration. Results showed SH225 raised pH by up to 0.89 unit under Cd stress and decreased Cd accumulation in roots and leaves by 30.39 % and 66.56 %, respectively. Cd speciation distribution data (including residual, adsorbed, and intracellular forms) demonstrated SH225's capacity to adsorb Cd, resulting in a 16.24 % reduction in residual Cd. SEM and TEM analyses corroborated these findings, illustrating substantial Cd adsorption by SH225 bacterial cell walls folding. Additionally, FTIR results highlighted the involvement of functional groups such as -OH, -NH2, CH2/CH3 bending, COO-, and PO during the adsorption process. In conclusion, the alkalizing bacterium SH225 has restricted the migration of Cd into plant tissues, thereby reducing the health risks associated with Cd exposure.

Highly efficient recovery of phosphate and fluoride from phosphogypsum leachate: Selective precipitation and adsorption

Phosphogypsum, a typical by-product in the phosphorus chemical industry, could generate a large amount of leachate containing phosphate and fluoride in the process of rainfall and long-term stacking, which not only causes serious environmental pollution, but also leads to a waste of resources. In this study, a united treatment of calcium hydroxide precipitation and lanthanum zeolite (La-ZFA) adsorption was proposed to achieve the recovery of phosphate and fluoride from phosphogypsum leachate. In phosphogypsum, most phosphorus could be leached except P in the residual occurrence form, while for fluoride, only water-soluble F could be effectively leached. The optimum leaching amounts of phosphate and fluoride were 22.59 and 4.64 mg/g, respectively, at liquid-solid ratio of 400:1, leaching time of 120 min, pH of 6.0, particle size of >200 mesh (<0.075 mm), and leaching temperature of 25°C. Using Ca(OH)2 as the precipitant, the phosphate could be precipitated selectively from phosphogypsum leachate by controlling pH and time, and the concentrations of it decreased significantly to 0.29 mg/L at pH 10.0, with a removal efficiency of 99.48%. XRD, SEM and Visual MINTEQ software analysis proved that the main component of the precipitate was hydroxyapatite (Ca5(PO4)3(OH)). After P precipitation, a series of sorbents for fluoride were investigated, and La-ZFA sorbent was chosen and utilized to recover the fluoride from the leachate through a cyclic fixed-bed column. The efficiency of La-ZFA was basically not affected by the high concentration sulfate, and it can selectively adsorb fluoride from phosphogypsum leachate, leading to a final fluoride concentration of 0.29 mg/L in the effluent. The characterization demonstrated that fluoride might be adsorbed onto the La-ZFA via ligand exchange with hydroxy groups. The proposed method in this study is expected to sequentially recover phosphate and fluorine from the leachate of phosphogypsum, and it has great guiding significance for resource utilization and management of phosphogypsum.

Residual squeeze-and-excitation convolutional auto-encoder for fault detection and diagnosis in complex industrial processes

Recently, deep learning has attracted increasing attention in process monitoring. However, it is still a big challenge to extract effective features of process data for fault detection and diagnosis (FDD) by using deep learning-based methods. In this study, a novel deep learning-based model, residual squeeze-and-excitation convolutional auto-encoder (RSECAE) is proposed for FDD in complex industrial processes. A hybrid structure that integrates convolution calculation and auto-encoder is proposed to construct multiple convolution layers and deconvolution layers in the encoder and decoder respectively. Thus, RSECAE can learn effective features from the process signals in an unsupervised manner. At the same time, multiple residual squeeze-and-excitation networks (RSENets) are embedded in the deep network, which effectively preserves the critical feature representations of the convolution layer and transmits them to the decoder in the form of residuals. Finally, maximum mean discrepancy (MMD) term is utilized in RSECAE to reduce the distribution difference between the process signals and the learned features. This enables RSECAE to extract effective features with prior distribution information. RSECAE provides a new solution for process FDD for complicated industrial processes. Two industrial cases are adopted to validate the effectiveness of the RSECAE in process FDD. The experimental results demonstrate the effectiveness and superiority of RSECAE in process fault detection and fault diagnosis.

Bio-availability of potential trace elements in urban dust, soil, and plants in arid northwest China

Potential trace elements pollution in cities poses a threat to the environment and human health. Bio-availability affects toxicity levels of potential trace elementss on organisms. This study focused on exploring the relationship between soil, plant, and atmospheric dust pollution in Urumqi, a typical city in western China. It aims to help reduce pollution and protect residents’ health. The following conclusions were drawn: 1) potential trace elementss like Cr, Pb, As, and Ni are more prevalent in atmospheric dust and soil than in plants. Chromium was in the first group, Cadmium and Mercury were in the second, and Plumb, Arsenic, and Nickel were in the third. Atmospheric dust and soil exhibit a significantly higher heavy metal content than plants. For example, The atmospheric dust summary Chromium content was up to 88 mg/kg. 2) Soil, atmospheric dust, and plants have the highest amount of residual form. Residual form had the highest percentage average of 53.3%, whereas Organic matter bound form had the lowest percentage of just 7.7%. The plants contained less residual heavy metal than the soil and atmospheric dust. 3) The correlation coefficient between the carbonated form content of Cd of soil and atmospheric dust is 0.95, which is closely related. Other potential trace elements show similar correlations in their bio-available contents in soil, plants, and atmospheric dust. This study suggests that in urban area, the focus should be on converting potential trace elements into residual form instead of increasing plants’ absorption of potential trace elements.