Degree Of Degradation Research Articles

Effect of Fe content on physical, tribological and photocatalytical properties of Ti-6Al-xFe alloys for biomedical applications

The aim of the current study is to evaluate the effect of iron content (0, 2, 4, 6 and 10 wt%) on the structural, tribological and photocatalytical properties of a nanostructured ternary alloy Ti-6Al-XFe, prepared by high energy milling. The alloys’ characteristics such as lattice parameters, powder morphologies, surface roughness, relative density/porosity, and microhardness, were evaluated using X-ray diffraction (XRD), scanning electron microscope (SEM), surface profilometry, porosimeter and micro durometer, respectively. The W-H method was utilized to determine the crystallite size. Micro strain was also calculated, which is produced in the lattice due to the diffusion of iron atoms. The photocatalytical characterization was conducted by measuring their absorbance as a function of time using spectrophotometer of visible and ultraviolet light in the wavelength range of 500–800 nm. The tribological characterization was performed using an oscillating tribometer under wet conditions, simulating the human body environment using Phosphate Buffered Saline (PBS) solution with neutral pH 7.4, under different applied loads of 2, 6 and 10 N, respectively. Results showed that the addition of Fe has a significant effect on the structural properties of the developed alloys. The lattice parameter (aα) decreased with increasing Fe content from 2.9493 Å (0 wt% Fe) to 2.9491 Å (10 wt% Fe), while the average grain size increased considerably from 6.965 nm (0 wt% Fe) to 44.42 nm (10 wt% Fe). The wear test results showed that, friction coefficient and wear rate considerably decreased due to the formation of protective films such as TiO2. The photocatalytical characterization showed that, the degradation of methylene blue (MB) increased with increasing Fe content. The Ti-6Al-4Fe -catalyst gave the best degree of degradation of 90.76% within 60 min, which meant that the decolorization process could be operated rapidly at a relatively low cost without UV irradiation.

Effects of crop residue incorporation on soil‐biodegradable mulch film degradation in a broccoli‐sorghum rotation system

AbstractSoil‐biodegradable mulch films are designed to be incorporated into the soil at the end of the crop cycle, to be degraded by soil microorganisms. Despite growing scientific interest, open‐field studies about the fate of these mulch films in soils are rare, with most research conducted in laboratories. We performed an open‐field trial to evaluate the effects of soil incorporation of both a combining a commercial soil‐biodegradable mulch film and broccoli and sorghum crop residues over two cropping seasons. The mulch film was sampled after broccoli harvesting and placed inside mesh bags that were buried horizontally or vertically at different depths. Film biodegradation was assessed by direct (CO2 emissions) and indirect indicators (film mass and area loss). Three experiments were conducted to evaluate (a) how incorporating crop residues affect mulch film degradation; (b) temporal changes of soil microbial activity after the incorporation of crop residues and mulch films; and (c) possible bias in the measurement of soil CO2 emissions due to horizontal vs. vertical mesh bag orientation. Incorporation of crop residues enhanced mulch film degradation and increased the soil esterase activity. However, abundance of soil fungi and bacteria in bulk soil was not increased by mulch film presence. Mesh bag orientation did not alter the soil CO2 efflux or affect the degradation degree of mulch films. Film in mesh bags buried at 10–15 cm depth showed greater degradation than those buried at 0–5 cm. Further in‐field studies are necessary to evaluate the effects of soil incorporation of residue from different crops and impacts of other associated management practices such as various soil tillage regimes.

Comprehensive assessment of degradation and methods of phytomelioration of low-yielding soils of the Volga region

In the Volgograd Region, more than 3.9 million hectares of agricultural land, including 2.1 million hectares of arable land (36%), and 1.8 million hectares of hayfields and pastures (64%), are subject to degradation and desertification to one degree or another. The article presents the results of a survey of the Trans-Volga region, by the percentage ratio of areas of low-yielding soils subject to degrading factors and calculations of a complex indicator of soil Dр. It was found that the low-productive lands of the Bykovsky district are subject to a moderate level of degradation (Dp = 0.94). An increased level of soil degradation was noted in the Mykolaiv and Staropoltavsky districts with a Dp equal to 0.91 and 0.89. A high level of degradation was detected in the Leninsky, Pallasovsky and Sredneakhtubinsky districts with Dp equal to 0.87, 0.86 and 0.83, respectively. In areas with a moderate level of degradation, a set of measures with superficial improvement is proposed. With an increased and high level of degradation, it is proposed to use root and surface improvement with the use of drought-resistant and halophytic vegetation. The results of calculations of the complex, indicator of the degree of degradation of low-yielding lands of the Volga region and the proposed methods of phytomelioration are the basis for making tactical decisions to reduce the impact of degradation factors on the soil.

Degradation of sulfamethazine in water in thermally activated persulfate process

BackgroundThe thermally activated persulfate (TAP) process was utilized to degrade sulfamethazine in water. MethodsThe effects of temperature, Na2S2O8 dosage, initial concentration of sulfamethazine, and the presence of salt (NaCl and NaNO3) and natural organic matter (humic acid) on the degradation of sulfamethazine in the TAP process were studied. Significant FindingsThe degradation of sulfamethazine in the TAP process was closely fitted by a pseudo-first-order kinetic model. At pH 6, the degree and rate of degradation of sulfamethazine at 70 °C considerably surpassed those at 40 °C with diverse Na2S2O8 dosages. At 70 °C and pH 6, raising the Na2S2O8 dosage from 1 mM to 8 mM increased the degree and rate of degradation of sulfamethazine; but excess Na2S2O8 (16 mM) limited them. However, lower temperatures eliminated this limitation. The degree and rate of degradation of sulfamethazine were higher at 70 °C and pH 6 when the initial concentration of sulfamethazine was lower. The Arrhenius equation was utilized to calculate the apparent activation energy at diverse Na2S2O8 dosages. The apparent activation energy for the degradation of sulfamethazine increased from 91 kJ/mol to 150 kJ/mol as the Na2S2O8 dosage was raised from 1 mM to 8 mM. However, the apparent activation energy for the degradation of sulfamethazine was reduced to 120 kJ/mol as the Na2S2O8 dosage was raised further to 16 mM. Radical quenching tests indicate that the most important radical in the degradation of sulfamethazine at 70 °C and pH 6 was SO4•−. At 70 °C and pH 6, the presence of salt (NaCl and NaNO3) and humic acid (HA) exhibited various influences on the degradation of sulfamethazine. The degree of degradation of sulfamethazine (10 mg/L) in the TAP process (70 °C and pH 6) reached 100% at 3 min at an Na2S2O8 dosage of 8 mM with a corresponding rate constant of 1.4003 min−1. Accordingly, the TAP process can be utilized in the effective treatment of sulfamethazine-contaminated water.

Anthocyanins degradation mediated by β-glycosidase contributes to the color loss during alcoholic fermentation in a structure-dependent manner

Anthocyanins deteriorate during fermentation to varying degrees depending on the structure of the anthocyanin, thus affecting the sensory quality of the wine, and the degradation of anthocyanins is closely associated with the β-glycosidase. In this study, the alcoholic fermentation systems containing cyanidin-3-O-glucoside (C3G), peonidin-3-O-glucoside (Pn3G), delphinidin-3-O-glucoside (D3G), petunidin-3-O-glucoside (Pt3G), and malvidin-3-O-glucoside (M3G) incubated for eight days. Our results indicated that the color of the systems containing different anthocyanins saw significant and dissimilar changes during fermentation, in relation to anthocyanin degradation. The five anthocyanins showed varying degradation degrees, which are relevant to theβ-glycosidase produced by yeast. Enzyme kinetics and molecular docking analysis showed the affinity between anthocyanins and β-glucosidase: C3G < M3G < Pn3G < Pt3G < D3G. This study demonstrated that β-glycosidase had distinct effects on anthocyanins with diverse structures, resulting in different color changes in fermentation systems. It provided a potential strategy for sensory quality improvement during the fermentation of fruit wines rich in anthocyanins.

Investigating earthquake-induced irregularity based on post-earthquake running performance analysis of track-bridge system

In evaluating post-earthquake damage to track-bridge systems, this study conducts nonlinear time history analysis on the CRTS II ballastless track simply-supported beam system subjected to transverse earthquake loading and explores the characteristics of residual displacement and stiffness degradation of the track-bridge system under transverse earthquakes. The effect of the earthquake-induced stiffness degradation of track-bridge systems on the dynamic performance of high-speed trains is investigated, and earthquake-induced dynamic irregularities are constructed to quantify the overall stiffness degradation degree of the track-bridge system. Furthermore, a reconstruction method for the earthquake-induced dynamic irregularity characteristic curve is proposed, considering probability guarantee rates. The research results indicate that the earthquake-induced dynamic irregularity can effectively quantify the running performance degree of high-speed trains under earthquake-induced stiffness degradation conditions. The transverse acceleration and derailment coefficient of high-speed trains increase as the ground motion intensity rises. The amplitude of the characteristic curve grows significantly with the increase in pier height.

Influence of ozone supply mode and aeration on photocatalytic ozonation of organic pollutants in wastewater using TiO2 and ZnO nanoparticles

Photocatalytic ozonation, which combines the effects of lighting and ozonation, has been shown to enhance the decolorization and degradation of organic pollutants in wastewater. Dye solutions with concentrations of 10 ppm for both methylene blue and methyl orange dyes were used. The influence of ozoneation on the performance of photocatalytic activity of TiO2 and ZnO nanoparticles for the removal of organic dyes from aqueous solutions was investigated. To evaluate their efficacy for the removal of methylene blue and methyl orange dyes from aqueous solutions, the photocatalysts were exposed to UV light for 90 min, with ozone supplied either intermittently or continuously by an SDBD cold plasma reactor. The photocatalysts utilized in this study were characterized using SEM and XRD techniques. The degree of color degradation was determined using UV–Vis spectroscopy. The results demonstrate that TiO2 and ZnO nanoparticles exhibit different degrees of photocatalytic activity for the two dyes. The addition of ozone was found to enhance both the color degradation and mineralization rates of the pollutants, with intermittent ozonation proving more effective than continuous ozonation. The most significant color degradation results were obtained using TiO2 nanoparticles with intermittent ozonation for methylene blue dye (97 %) and ZnO nanoparticles with intermittent ozonation for methyl orange dye (40 %). Overall, this study provides evidence that photocatalytic ozonation represents a promising technique for water treatment.

Comparison of freezing and heating treatment sequence on biochemical properties and flavor of swimming crabs (Portunus Trituberculatus) meat during freeze-thaw cycles

The objective of this study was to compare the effect of freezing and heating treatment sequences on the biochemical properties and flavor of crab (Portunus trituberculatus) meat during freeze-thaw cycles. The results showed that pH, color, K and microstructure changes in the H-F group were not significant with increasing number of freeze-thaw cycles, but TVB-N values increased and WHC values decreased. However, with the increase in the number of freeze-thaw cycles, pH and WHC significantly decreased and TVB-N, L* and K values significantly increased in the C and F-H groups. Proteins were degraded in all groups, but the lower degree of degradation occurred in the H-F group. Although the total free amino acid content decreased with increasing number of freeze–thaw cycles in each group, the high content of AMP and IMP in the H-F group suggested that it still had a better flavor.

The effect of long-term operation on fatigue and corrosion fatigue crack growth in structural steels

Operational degradation of steels under a combined action of mechanical loading and aggressive hydrogenating environments is a crucial problem for structural integrity. Among the mechanical properties, the characteristics of brittle fracture resistance, namely, impact strength and fracture toughness, as well as the plasticity characteristics, are highly sensitive to the operational degradation of structural steels. However, in the case of exposing of structures beside environmental influences to cyclic mechanical loading scenarios, their reliability depends on the degradation degree due to fatigue and corrosion fatigue. Tendency of in-service changes in the fatigue characteristics (fatigue crack growth rate and fatigue strength) can be unambiguous. In-service lifetime of structure due to the non-monotonic character of operational degradation of certain mechanical characteristics is divided into two stages: deformation strengthening (stage I) and in-bulk dissipated damaging (stage II). The operational degradation of steels is accelerated under influence of corrosive hydrogenating environments as a result of intensification of dissipated damaging. The effect of environments on acceleration of fatigue crack growth rate is mainly revealed in the mid-region of stress intensities, more significantly for in-service degraded metal, indicating its susceptibility to stress corrosion fatigue.

Effects of thermal cycling treatment on load bearing and friction behavior of SiCp/A356 composites

During bench tests and actual service, the Al-MMC (metal matrix composite) brake discs used in urban rail transit vehicles experienced problems such as poor wear resistance, compromising the brake discs' stability and safety. While braking, the brake disc material will bear the thermal cycling loads, leading to a certain degree of degradation in the material's performance. In this study, the degradation of the material's performance by the thermal cycling treatment was investigated. The results showed that all material performance degraded to some extent after thermal cycling treatment, with a strong correlation with cycling temperature. The degradation of material performance was caused by a combination of matrix mechanical damage and interface damage. At the same time, the tribological performance of the material also decreased to some extent. The main effect of thermal cycling treatment on tribological performance was its effect on material performance. The increase of hard particles in the abrasive debris resulting from the mechanical damage of the material and the aggravation of the dynamic changes in the TBL (third body layer) were the basic reasons for the surface scratches. The results further help to explore the application of Al-MMCs in high-temperature and long-term service.

Impacts of long-term organic manure inputs on cultivated soils with various degradation degrees

With an increasing concern of soil health and sustainable development, organic manure application has been readdressed in recent years. In Northeast China, the agricultural industry is highly developed and organic manure resources are abundant, but soil degradation is serious due to extensive expansion of cultivation. Currently, limited information is available on how soils with various degradation degrees respond to long-term manure fertilization. Given that, a comparative study was conducted based on soil functional assessment of croplands with over 35 years of manure fertilization (maize straw compost, SA; cattle manure, CA) and various degradation degrees (none, light, moderate, and heavy). Soils in these croplands were loess-derived Mollisols and concentrated on a gentle to flat slope. Except for the difference in manure fertilization (SA and CA), similar field managements were adopted for these croplands during the past 35 years. Results showed that the impacts of erosion degradation and manure fertilization on soil physical structure lasted across the whole profile (0 ∼ 120 cm), while their impacts on soil nutrient properties were concentrated in shallow layers (<50 cm). Meanwhile, erosion degradation dominated 17.9% of the variance of soil physical structure, and soil profile depth contributed to 15.9% of soil nutrient variation. According to field validation regarding soil erosion modulus and crop yield, principal component analysis (PCA) with a nonlinear scoring method showed a good performance on the integrated soil functional index (ISI) assessment in this study area. The ISI of these croplands was found to be minimally characterized by BD, SOC, TN, AK, sand content, and CEC (R2 >0.64, p < 0.001). In addition, manure fertilization could significantly improve the ISI and maize yield for degraded soils, but had a slight impact on these two indicators for non-degraded soils. In terms of contribution to ISI improvement, SA (1.79% ∼ 283.73%) generally outperformed CA (4.53% ∼ 212.83%), while the latter was more effective in altering soil structure in deep layers (>70 cm). Generally, the ISI and maize yield were more susceptible to erosion degradation than manure fertilization. The obtained results provide useful information for a better cropland management in Northeast China.

Habitat Quality Assessment and Driving Factor Analysis of Xiangyu in Feng River Basin Based on InVEST Model

Analyzing the evolution of regional habitat quality is an important means to assess the impact of engineering activities on ecosystems. Taking Xiangyu in the Feng River Basin as the study area, the land use change in 1985 and 2022 was analyzed, and the habitat quality and degradation degree were evaluated by using the Integrated Assessment and Tradeoff of Ecosystem Services (InVEST) model. The results showed that from 1985 to 2022, the transfer of land use types in Xiangyu mainly occurred on dry land, bare land, forest land, and industrial land. The area of dry land and bare land converted into industrial land is 10,825.15 m2 and 249,123.09 m2, respectively, and affected by the measures of returning farmland to forest and grassland in Shaanxi Province, the area transferred to forest land reached 371,471.87 m2, mainly from dry land and bare land. The continuous expansion of industrial land led to a significant decline in habitat quality, and the areas with high habitat degradation were concentrated in forest land in a large range, which indicated that forest land was vulnerable to industrial land expansion. Land use change and human engineering activities are the main factors affecting the ecological environment, and limiting the expansion rate of industrial land is the key to protecting the ecological environment.

Estimation of the Degradation of Epoxy Resin due to Void Discharge using Weighted SVM and Partial Discharge Characteristics

The performance and reliability of power apparatus are affected by the degradation of electrical insulation, often caused by voids in resin‐molded components. To address this issue, we investigated the use of machine learning to estimate the degree of degradation due to void discharges in epoxy resin. We prepared samples with artificial void defects and collected partial discharge data up to the dielectric breakdown, applying long‐term AC voltage. Utilizing this data, a machine learning model was developed to estimate degradation levels. The results showed that the accuracy was 55% and the false estimation rate which underestimates the degradation level was as high as 31%, which was a significant problem for practical use. Therefore, for regions of data that were difficult to classify, we constructed a weighted SVM model that predicted higher levels of degradation by weighting the data according to their degradation labels. With this approach, the accuracy remained at 57%, but the rate of underestimation of the degree of degradation was reduced to only 4%. Consequently, we were able to develop an effective estimation model that is practical for the maintenance of power apparatus. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

Revealing the accelerated crack prolongation behavior under chemical ionomer degradation within the catalyst layer

As a critical electrochemical reaction region of the proton exchange membrane fuel cell (PEMFC), the cracking issue of the catalyst layer (CL) considerably affects the performance and durability of the PEMFC. However, the impact of chemical ionomer degradation on CL cracking has not been comprehensively revealed. This study investigates the effect of chemical ionomer degradation on CL cracking through accelerated stress tests, characterization, and theoretical analysis. The results indicate that the increasing chemical degradation degree facilitates CL cracking. The CL with the most severe chemical degradation has a single total crack length increment of 1.97 times for the novel CL under the same degree of mechanical degradation. CL fracture resistance analyses reveal that the decrease in interface fracture resistance is the predominant impulse in accelerating CL cracking. Furthermore, the cell voltage reduction of the CL with the most severe chemical degradation during mechanical degradation is 34.22 mV at the current density of 1800 mA cm−2, which is 1.82 times for the fresh CL. The increment of activation resistance and mass transfer resistance are the main causes of the larger cell performance loss. The above findings emphasize the significance of high interface fracture resistance in inhibiting CL cracking and offer theoretical support for analyzing post-operational CL cracking.

Mango peel as a potential enzyme inducer in Trichoderma harzianum

Water-insoluble exopolysaccharides (I-EPS) are a virulence factor for dental biofilms. It has already been demonstrated that mango pulp induces the secretion of glucan-hydrolytic enzymes in the fungus Trichoderma harzianum, and that they have an effect on I-EPS from young biofilms. Aim: Evaluate the effect of mango peel as an enzyme inducer in T. harzianum, and the effect of enzymes secreted on mature biofilms. Methods: Fractions of the peel (PL) and ethanol-precipitated pulp (PP) of Tommy Atkins mangoes were sterilized and added to a culture medium containing T. harzianum for induction of hydrolytic enzymes. After 192 h, the culture medium was centrifuged and the supernatant (enzyme extract) was used as treatment on S. mutans biofilms (n=9): a) NaCl 0.9 %; b) 0.12 % chlorhexidine digluconate; and c) extract of enzymes induced by PL or PP. Acidogenicity, bacterial viability, quantification of insoluble polysaccharides, and three-dimensional analysis of the biofilm by scanning electron microscopy (SEM) was performed. Data were analyzed by ANOVA followed by the Tukey test (α=5 %). Results: The hydrolytic enzymes did not alter the metabolism or bacterial viability of the biofilm (p&lt;0.05). Although the images obtained by SEM suggest some degree of matrix degradation, the quantification of I-EPS for the PL and PP groups did not differ from the control group (p&gt;0.05), suggesting a slight effect on the disorganization of the mature S. mutans biofilm. Conclusion: The results suggest that mango peel fraction can induce secretion of mutanase by T. harzianum, however in an insufficient amount to generate significant degradation on cariogenic biofilm.

A Diagnostic Method for the Saturable Reactor Core Looseness Degree of Thyristor Converter Valves

During the long-term operation of thyristor converter valves, the saturable reactor vibration (mainly caused by magnetostriction) will lead to core looseness faults. In order to accurately evaluate the fault degradation degree, this paper proposes a vibration signal recognition model for iron core looseness based on synchrosqueezed wavelet transforms and a convolutional neural network. Firstly, vibration experiments are conducted on saturable reactors to obtain signals under different core looseness degrees. Then, the spectrogram features of vibration signals are extracted using synchrosqueezed wavelet transform. Finally, based on the high-dimensional learning ability of convolutional neural networks, the fault characteristics of the spectrogram are mined to accurately identify the core looseness degree. The research results indicate that the model in the paper has higher recognition accuracy than some other methods, which provides convenience for the monitoring and maintenance of saturable reactors.

Efficient Performance Prediction of End-to-End Autonomous Driving Under Continuous Distribution Shifts Based on Anomaly Detection

A Deep Neural Network (DNN)’s prediction may be unreliable outside of its training distribution despite high levels of accuracy obtained during model training. The DNN may experience different degrees of accuracy degradation for different levels of distribution shifts, hence it is important to predict its performance (accuracy) under distribution shifts. In this paper, we consider the end-to-end approach to autonomous driving of using a DNN to map from an input image to the control action such as the steering angle. For each input image with possible perturbations that cause distribution shifts, we design a Performance Prediction Module to compute its anomaly score, and use it to predict the DNN’s expected prediction error, i.e., its expected deviation from the ground truth (optimal) control action, which is not available after deployment. If the expected prediction error is too large, then the DNN’s prediction may no longer be trusted, and remedial actions should be taken to ensure safety. We consider different methods for computing the anomaly score for the input image, including using the reconstruction error of an Autoencoder, or applying an Anomaly Detection algorithm to a hidden layer of the DNN. We present performance evaluation of the different methods in terms of both prediction accuracy and execution time on different hardware platforms, in order to provide a useful reference for the designer to choose among the different methods.

Does the Validity of the Environmental Kuznets Curve Postulation Empirically Depend on the Level of Human Development in Africa?

Purpose: The interconnectedness between human development and environmental degradation is a complex issue that warrants investigation in Africa. Although there are a few studies on the economic growth and environmental degradation nexus for African countries, there is a huge scarcity of empirical research that explores the Environmental Kuznets Curve (EKC) postulation in the context of human development and environmental degradation in Africa. The study therefore empirically explored the relationship between Human Development and Environmental Degradation within the framework of the EKC using 50 African countries subdivided into High Human Development Index Countries (HHDICs), Medium Human Development Index Countries (MHDICs) and Low Human Development Index Countries (LHDICs) from 2000 to 2019. Data for the study were obtained from the World Bank’s development indicators and the Human Development Reports of the United Nations Development Programme (UNDP-HDR).&#x0D; Methodology: The study made use of the Panel Corrected Standard Error (PCSE) model and the Feasible Generalised Least Squares Regression model (FGLS) which are econometrically suitable to handle N &gt; T and T &gt; N panels respectively, and are both robust to cross sectional dependence, contemporaneous correlation, group wise heteroscedasticity and slope heterogeneity. Other econometric techniques such as Descriptive Statistics, Correlation Analysis, Variance Inflation Factor test (Multicollinearity), second generation unit root tests (CADF and CIPS), Durbin Watson, Breusch Godfrey tests (Serial Correlation) and the White Test (Heteroscedasticity) were also employed in the study.&#x0D; Findings: The empirical results produced evidence that the data is integrated of order one I(1) and exhibits cross sectional dependence, slope heterogeneity and cointegration. The data was also found to be serially correlated and heteroscedastic. However, multicollinearity was absent. The panel estimates of the PCSE and the FGLS estimators showed that Human Development is a key driver of Environmental Degradation in Africa, with the greatest proportion of the impact on HHDICs, followed by MHDICs and then finally LHDICs. The results also revealed the validity of the EKC postulation only in the HHDICs, evidenced by the presence of an inverted U-shaped relationship between Environmental Degradation and Human Development. In The LHDICs and MHDICs on the other hand, U-shaped relationships between Environmental Degradation and Human Development were found, signalling the invalidity of the EKC. There was significant evidence for the support of the feedback hypothesis between Human Development and Environmental Degradation in HHDICs, MHDICs, LHDICs and all the 50 African countries at large. Based on the findings, Policymakers were given recommendations that took into consideration the uniqueness of the economic situations in HHDICs, MHDICs, LHDICs and Africa as a whole.&#x0D; Recommendations: The study shows that the degree of environmental degradation is proportional to the level of human development in Africa and indicates that the validity of the EKC postulation in the context of human development) is exclusive to only the HHDICs in Africa. This provides an incentive for policy makers in the MHDICs and LHDICs of Africa to make human development a priority through industrialisation and other profitable economic activities. This is likely to help them afford innovations and technological developments that protect the environment through the greater use of cleaner energy than the naturally abundant fossil fuel as well as the institutionalisation of policies that protect the environment as human development appreciates.

Effect of Rhodococcus bioaugmentation and biostimulation on dibenzothiophene biodegradation and bacterial community interaction in petroleum-contaminated soils

Bioremediation can be effective method for achieving polycyclic aromatic hydrocarbons (PAHs) degradation in soil contaminated with petroleum. The aim of this study was to compare the effect of Rhodococcus bioaugmentation (BIOE) and biostimulation (BIOS) on dibenzothiophene biodegradation and bacterial community interaction in petroleum-contaminated soils. The findings revealed that compared to natural degradation treatment (NAT) and BIOS, BIOE had the highest dibenzothiophene (DBT) and the majority of DBT degradation occurred within the first 30 days. BIOS had a positive impact in the early stage but an opposite effect in the later stages for degrading DBT. Beta diversity analysis revealed significant differences of bacterial composition among NAT, BIOS, and BIOE. Sequencing results indicated that Bacillus and Paenibacillus were dominant genera involved in DBT degradation. Network analysis revealed co-occurrence patterns and connectivity, with BIOE exhibiting higher connectivity and the highest number of links in BIOS. In summary, Rhodococcus bioaugmentation was the simplest and effective method to enhance the clustering degree of bacterial network and DBT degradation in petroleum-contaminated soil, compared to NAT and BIOS.

An Image Arbitrary-Scale Super-Resolution Network Using Frequency-domain Information

Image super-resolution (SR) is a technique to recover lost high-frequency information in low-resolution (LR) images. Since spatial-domain information has been widely exploited, there is a new trend to involve frequency-domain information in SR tasks. Besides, image SR is typically application-oriented and various computer vision tasks call for image arbitrary magnification. Therefore, in this article, we study image features in the frequency domain to design a novel image arbitrary-scale SR network. First, we statistically analyze LR-HR image pairs of several datasets under different scale factors and find that the high-frequency spectra of different images under different scale factors suffer from different degrees of degradation, but the valid low-frequency spectra tend to be retained within a certain distribution range. Then, based on this finding, we devise an adaptive scale-aware feature division mechanism using deep reinforcement learning, which can accurately and adaptively divide the frequency spectrum into the low-frequency part to be retained and the high-frequency one to be recovered. Finally, we design a scale-aware feature recovery module to capture and fuse multi-level features for reconstructing the high-frequency spectrum at arbitrary scale factors. Extensive experiments on public datasets show the superiority of our method compared with state-of-the-art methods.