Degree Of Degradation Research Articles

Processing and Characterization of Spent Nickel-Metal Hydride Type AA Batteries to Recover Valuable Materials (Cobalt, Nickel and Rare Earth Elements).

The experimental research was focused on the investigation of valuable material from spent Ni-MH type AA batteries, namely the metal grid anodes and the black mass material (anode and cathode powder). The materials of interest were analyzed by X-ray fluorescence spectroscopy (XRF), ICP-OES (inductively coupled plasma optical emission spectrometry), optical microscopy, scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), electron backscatter diffraction (EBSD), and X-ray diffraction (XRD). The analyzed grids have a high Fe content, but some of them correspond to the Invar alloy with approx. 40% Ni. In the black mass material, round particles and large aggregations were observed by SEM analysis, showing a high degree of degradation. The XRD analysis reveals the presence of only three compounds or phases that crystallize in the hexagonal system: La0.52Ce0.33Pr0.04Nd0.11Co0.6Ni4.4, Ni(OH)2, and La5Ni19. The obtained results provide useful and interesting information that can be used for further research in the recycling and economic assessment of metals from spent Ni-MH batteries.

Genomic Multicopy Loci Targeted by Current Forensic Quantitative PCR Assays

Modern forensic DNA quantitation assays provide information on the suitability of a DNA extract for a particular type of analysis, on the amount of sample to put into the analysis in order to yield an optimal (or best possible) result, and on the requirement for optional steps to improve the analysis. To achieve a high sensitivity and specificity, these assays are based on quantitative PCR (qPCR) and analyze target DNA loci that are present in multiple copies distributed across the genome. These target loci allow the determination of the amount of DNA, the degree of DNA degradation, and the proportion of DNA from male contributors. In addition, internal control DNA of a known amount is analyzed in order to inform about the presence of PCR inhibitors. These assays are nowadays provided as commercial kits that have been technically validated and are compatible with common qPCR instruments. In this review, the principles of forensic qPCR assays will be explained, followed by information on the nature of DNA loci targeted by modern forensic qPCR assays. Finally, we critically draw attention to the current trend of manufacturers not to disclose the exact nature of the target loci of their commercial kits.

Seismic performance of Li-Tie type brick masonry infilled wooden frames considering joint damage: Degradation mechanism and hysteretic model

This paper investigated the influence of the damage to column-foot (C-F) joints and the gaps of mortise-tenon (M-T) joints on the seismic behavior of Li-Tie style timber frames with masonry-infilled wall. Five full-scale Li-Tie type brick masonry-infilled timber frames, two without the joint damage, two with the damage to C-F, and one with the gaps of M-T joints, were cyclically tested. The failure modes, mechanical and deformation mechanisms were revealed. The second-order effect, strength degradation law, and the changing laws of the equivalent viscous damping coefficient and strain of the specimens were analyzed. The results showed that when the maximum inter-layer drift ratio was less than 2.4 %, the second-order effect of Li-Tie type timber structure with the masonry infill can be ignored. The masonry infilled timber frames considering the joint deterioration suffered a large strength degradation degree, and a more significant loss of the peak load and ductility. The equivalent viscous damping coefficient of the masonry infilled timber frame considering C-F damage increased by up to 24.67 %, while that of the one including the gaps of M-T joint decreased by 6.67 %. The C-F damage led to an increase in the strain at the beam end, the damage to M-T joint resulted in an decrease in the strain at the beam end. However, the damage to C-F and the gaps in M-T joint had little influence on the strain distribution in the C-F area. Based on the hysteretic, stiffness and strength degradation characteristics, and tests results of the specimens, the new tri-linear hysteretic models of Li-Tie type brick masonry infilled wooden frames with and without the joint damage were established and verified. Good agreement between the model predictions and test results was observed.

An aero-engine remaining useful life prediction model based on clustering analysis and the improved GRU-TCN

Abstract Accurately predicting the remaining useful life (RUL) of engines is paramount for implementing effective preventive maintenance strategies, preventing injuries and fatalities caused by equipment failures, and significantly reducing routine repair and replacement costs. However, existing deep learning models often ignore the variable operating conditions in real engineering applications and do not sufficiently consider the interaction between time series and degradation laws, which directly leads to the inability to effectively extract to degradation feature extraction. To address this problem, this study developed a novel combined network model named CA-DRGRU-TTCN, aimed at accurately predicting the RUL of engines. Firstly, a Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm is used to identify multiple operating conditions, and incorporate the recognition results into the model as additional new features. The first degradation time point is determined by JS divergence. Secondly, the deep connectivity of the residual Gated Recurrent Unit (GRU) module is designed to extract deeper degradation features, and an improved TMSE loss function based on the first degradation time point is applied to Temporal Convolutional Networks (TCN) to better capture the dependency between the time series and the real degradation degree of the engine. Finally, experiment results on the C-MAPSS dataset show that the proposed method achieves better performance compared to existing state-of-the-art methods.

Effects of alpine meadow degradation on the soil physical and chemical properties in Maqu, China

While alpine meadow degradation presents a significant ecological challenge, research on the complex patterns of soil property changes induced by degradation has been somewhat limited. In this study, we investigated the Maqu alpine meadow, meticulously categorizing it into different grassland types exhibiting varying degrees of degradation based on factors such as vegetation coverage and community, soil characteristics, and landscape features. These classifications included typical grassland, degraded grassland, desertified grassland, and sandy land. In August 2018, we established three quadrats at each sample point and collected soil samples at five depths (surface [0–2 ​cm], 2–5 ​cm, 5–10 ​cm, 10–20 ​cm, and 20–40 ​cm) to analyze soil particle size distribution (PSD) and nutrients content. The results revealed a discernible trend: alpine meadow degradation led to selective loss of nutrient-rich soil fine particles, resulting in significant alterations in soil PSD and nutrients, particularly pronounced in grasslands with low degrees of degradation. Moreover, within a specific range of degradation degree, the clay content in the shallow soil of alpine meadow increased with the degradation degree, but it declined when the degradation degree exceeded a certain threshold. Degradation also disrupted the intricate relationship between soil nutrients, with notable variations in their coupling. This difference was also reflected in the influence of soil physical and chemical properties on soil nutrients, with the explanatory power of each environmental indicator on soil nutrients decreasing significantly with increasing degradation. This study systematically analyzed the variation in soil physical and chemical properties throughout the degradation process, revealing the mechanism of soil nutrient imbalance and decline caused by the degradation process. It provides crucial theoretical foundations and reference points for the preservation and rejuvenation of alpine meadows, enriching the methodology for assessing the impact of grassland degradation.

Preparation of eco-friendly ULTCC materials with tailored coefficient of thermal expansion

Eco-friendly ultralow temperature co-fired glass-ceramic (ULTCC) materials were prepared at a sintering temperature of 650 °C using waste borosilicate glass as the raw material. The effects of co-doping with K2O and BaO on the thermal expansion coefficient (CTE) and dielectric properties of the glass-ceramics were investigated, and the relationship between structure and performance of the ULTCC material was studied and discussed. Additionally, the surface degradation characteristics of the series of samples in citric acid solution were examined. The results showed that K2O and BaO co-doping to ULTCC promoted crystallization, facilitated the transformation of quartz to cristobalite, adjusted the CTE, and significantly improved the dielectric properties of ULTCC. All samples exhibited a certain degree of degradation on their surfaces after immersion in citric acid solution; the degradation experiment of the samples after silver coating demonstrated the feasibility of recovering valuable metal electrodes from electronic components fabricated with this glass-ceramic. This study has positive implications for the development of green and cost-effective electronic packaging materials using waste glass, as well as for the environmentally friendly disposal of waste electronic components.

Impact of Reservoir Heterogeneity on Bitumen Content in the Mackay River Oil Sands, Athabasca (Canada)

AbstractThe Lower Cretaceous Manville Group of Upper McMurray Formation is one of the main bitumen reservoirs in Athabasca. In this study, the relationship between reservoirs heterogeneity and bitumen geochemical characteristics were analyzed through core and microscopic observation, lab analysis, petrophysics and logging data. Based on the sedimentology framework, the formation environment of high‐quality oil sand reservoirs and their significance for development were discussed. The results indicate that four types lithofacies were recognized in the Upper McMurray Formation based on their depositional characteristics. Each lithofacies reservoirs has unique physical properties, and is subject to varying degrees of degradation, resulting in diversity of bitumen content and geochemical composition. The tidal bar (TB) or tidal channel (TC) facies reservoir have excellent physical properties, which are evaluated as gas or water intervals due to strong degradation. The reservoir of sand bar (SB) facies was evaluated as oil intervals, due to its poor physical properties and weak degradation. The reservoir of mixed flat (MF) facies is composed of sand intercalated with laminated shale, which is evaluated as poor oil intervals due to its poor connectivity. The shale content in oil sand reservoir is very important for the reservoir physical properties and bitumen degradation degree. In the context of regional biodegradation, oil sand reservoirs with good physical properties will suffer from strong degradation, while oil sand reservoirs with relatively poor physical properties are more conducive to the bitumen preservation.

Assessing the potential of olive mill solid waste as feedstock for methane and volatile fatty acids production via anaerobic bioprocesses

The extensive production of olive mill solid waste (OMSW) from olive oil industry in the Mediterranean basin claims effective treatments and valorization strategies. This study aims to elucidate the potential of anaerobic digestion (AD) and anaerobic fermentation (AF) to convert pre-treated OMSW into biogas (CH4) and volatile fatty acids (VFA), respectively. The two thermal treatment conditions (65 °C and 180 °C) that are being implemented in the industry that manages the OMSW were tested. Comparing the two treatments aims to demonstrate the influence on the AD process of the degree of solubilization and degradation of the metabolites produced from the same substrate. AD of OMSW treated at low-temperature (65 °C) exhibited similar methane yields (195 ± 8 mL CH4/g volatile solid (VS)) to raw OMSW. AD of the solid phase (SP) after high-temperature treatment with acid addition at 180 °C resulted in methane yields comparable to raw OMSW while the liquid phase (LP) exhibited low methane yields (85 ± 10 mL CH4/g VS). Nevertheless, LP/180 °C exhibited the highest VFA bioconversion at 27.6 %, compared to less than 10 % for SP/180 ºC, SP/65 °C, and raw OMSW. The VFA profile showed notable variations with thermal treatment temperatures. Propionic acid dominated at SP/65 °C, while acetic acid became the primary VFA at 180 °C. Furthermore, significant degradation rates of phenolic compounds and furans were observed during the final day of both anaerobic processes. Overall, these findings suggest that AD is more suitable for raw OMSW, treated at low temperature and SP at high temperature, while AF offers a promising alternative for high-temperature-treated LP.

Biodegradation of <i>n</i>-Alkanes in Oil-Contaminated Bottom Sediments under Bioelectrochemical Stimulation

Degradation of oil hydrocarbons artificially introduced into bottom sediments in a bioelectrochemical system of a membrane-free (silt) type was studied. Passive bioelectrochemical stimulation by means of electrodes connected by an external circuit with a resistance of 1 kΩ, with an average electric current of ~85 µA was found to cause an increase in degradation during two months from 23.0 to 57.9%. Contamination of bottom sediments with oil (1.32 g/kg) slightly decreased the current in the external circuit of the bioelectrochemical system. The relationship was revealed between the degree of oil degradation and predominant utilization of the lighter n-alkanes in the C14H30–C30H62 series, compared with both the original oil and the residual hydrocarbons of the control. An increase in the representation of the alkB alkane monooxygenase genes relative to the 16S rRNA gene in the total DNA isolated from the sediments was induced by the introduction of hexadecane, both in the case of electrochemical stimulation and in the control. The results may be of interest for the development of new methods of bioelectrochemical removal of organic pollutants from anaerobic environments.

Structural and molecular modifications of woody biomass under minimal torrefaction conditions toward making durable pellets

Extensive research has been published on pelletizing severely torrefied biomass with the aid of binders, but limited studies have investigated the structural modifications of biomass during mild torrefaction. This study investigates the effects of several combinations of minimal torrefaction temperatures (230°C and 250°C) and relatively short durations (10, 15, and 30 minutes) on the thermophysical and molecular structure of the model woody biomass loblolly pine (Pinus Taeda) residues. The low severity treated biomass is compared with the untreated biomass and the biomass torrefied at 270°C for 30 minutes. Structural characterization methods include laser diffraction for particle size distribution and Brunauer-Emmett-Teller (BET) analysis to evaluate specific surface area. Additionally, FTIR, XRD, and TGA are used to assess changes in crystallinity and thermochemical composition. The woody residue torrefied at 250°C for 10 minutes exhibited a higher BET surface area (4.7 m²/g) than torrefied at 250°C for 15 minutes (3.5 m²/g). At a constant temperature of 250°C, the crystallinity index increases with the treatment duration, emphasizing the effect of time on retaining more hydroxyl groups that may act as binders for pelletization. This study demonstrates that minimizing the combination of torrefaction time and temperature can help control the degree of biomass molecular structure degradation thus minimizing overall mass loss, offering potential applications in the emerging biocarbon pellet industry.

An open-source fine-tuned large language model for radiological impression generation: a multi-reader performance study

BackgroundThe impression section integrates key findings of a radiology report but can be subjective and variable. We sought to fine-tune and evaluate an open-source Large Language Model (LLM) in automatically generating impressions from the remainder of a radiology report across different imaging modalities and hospitals.MethodsIn this institutional review board-approved retrospective study, we collated a dataset of CT, US, and MRI radiology reports from the University of California San Francisco Medical Center (UCSFMC) (n = 372,716) and the Zuckerberg San Francisco General (ZSFG) Hospital and Trauma Center (n = 60,049), both under a single institution. The Recall-Oriented Understudy for Gisting Evaluation (ROUGE) score, an automatic natural language evaluation metric that measures word overlap, was used for automatic natural language evaluation. A reader study with five cardiothoracic radiologists was performed to more strictly evaluate the model’s performance on a specific modality (CT chest exams) with a radiologist subspecialist baseline. We stratified the results of the reader performance study based on the diagnosis category and the original impression length to gauge case complexity.ResultsThe LLM achieved ROUGE-L scores of 46.51, 44.2, and 50.96 on UCSFMC and upon external validation, ROUGE-L scores of 40.74, 37.89, and 24.61 on ZSFG across the CT, US, and MRI modalities respectively, implying a substantial degree of overlap between the model-generated impressions and impressions written by the subspecialist attending radiologists, but with a degree of degradation upon external validation. In our reader study, the model-generated impressions achieved overall mean scores of 3.56/4, 3.92/4, 3.37/4, 18.29 s,12.32 words, and 84 while the original impression written by a subspecialist radiologist achieved overall mean scores of 3.75/4, 3.87/4, 3.54/4, 12.2 s, 5.74 words, and 89 for clinical accuracy, grammatical accuracy, stylistic quality, edit time, edit distance, and ROUGE-L score respectively. The LLM achieved the highest clinical accuracy ratings for acute/emergent findings and on shorter impressions.ConclusionsAn open-source fine-tuned LLM can generate impressions to a satisfactory level of clinical accuracy, grammatical accuracy, and stylistic quality. Our reader performance study demonstrates the potential of large language models in drafting radiology report impressions that can aid in streamlining radiologists’ workflows.

A transcontinental threat: Plastic waste from Africa invades Brazil's coast

Identifying the origin of plastic pollution is essential for the development of effective preventive and mitigatory strategies and guidelines for companies, governments, and stakeholders. In 2022, a considerable amount of plastic waste stranded on beaches of the northeastern coast of Brazil. A preliminary analysis of this waste revealed that most of the items were likely foreign made, and a brand auditing approach was applied to identify the brands, parent companies, and potential origin of the plastic waste. The items were also examined to determine their degree of degradation, polymer resin codes, colors, and probable uses. Given their probable foreign origin, a numerical simulation was employed using the OpenDrift dispersion model to determine the likely route each item would have taken before reaching the Brazilian coast. The brand audit confirmed that most of the plastic waste came from Africa (78.5 % of the items), followed by Brazil (15.7 %), and other nations (5.8 %). A total of 31 brands from seven African countries were identified, of which, >90 % originated from the Democratic Republic of the Congo. Drift simulations were consistent with the results of the brand audit, indicating that the plastics originated from the west coast of African, primarily between latitudes 5° N and 10° S. This analysis indicated that the Congo river was the principal source of the plastic waste that found its way to the Brazilian beaches. The present study highlights the widespread occurrence of plastic pollution across the Atlantic Ocean and underscores the need for mitigatory and regulatory measures that consider foreign sources, as well as local drivers of pollution. In this context, continuous monitoring programs will be essential to advance our understanding of the magnitude of the international plastic pollution problem, and provide insights to delineate specific enforcements dealing with this issue.

An improved similarity-based RUL prediction method considering degradation degree of multiple condition monitoring parameters for aero-engines

Abstract The aero-engine is the heart of an airplane. Predicting the remaining useful lifetime (RUL) of an aero-engine bears great significance, not only for improving the reliability and safety of the aero-engine but also for ensuring aircraft safety and performance. However, both issues, namely the selection of uncorrelated parameters for RUL estimation and the lack of a standard theoretical methodology for Health Index (HI) construction, inevitably impact the prediction accuracy. Here, we proposed an improved similarity-based RUL prediction method considering the degradation degree of multiple condition monitoring parameters for aero-engines. This method includes the improved minimum-redundancy maximum-relevancy approach for the quantitative selection of key parameters, and the similarity matching approach which takes into account the degradation degree of multiple parameters instead of constructing HI. The effectiveness of the proposed method was evaluated on turbine engine datasets. Experimental results show that (1) compared with other feature selection methods, the root mean square error (RMSE) of the proposed method is reduced by 12.3%; (2) compared with other RUL prediction methods, the RMSE of the proposed method is smaller than most methods but without a complicated training process. The results demonstrate that the proposed method achieves highly competitive prediction performance. By employing the proposed method, it is possible to significantly reduce the risk of engine failures, thereby improving safety and economic efficiency.

Analytical Spectral Semi-quantitative Dating Method of Printed Text Toner Using Raman Spectroscopy and the Fluorescence signal of Paper Sheet Cellulose

Abstract: The chemical processes that occur during the surface degradation of document paper under the influence of external factors were studied by Raman spectroscopy. The possibility of comparing the same processes occurring on clean free paper and under printed text toner letters is of interest. It is assumed that the transformation of cellulose can occur at different rates in the areas of paper exposed to direct atmospheric and light exposure and in the areas containing an intermediate layer of the toner. The most stable temporal changes occur in the region of C–C–C and C– C–O vibrations of glycosidic rings in the short-wavelength region of the Raman spectrum. Background: The main areas of research in the field of document dating, mainly focused on chromatographic methods. These methods are based on studying the dynamics of evaporation of volatile ink components. There is also a variety of chromatography techniques, including gas chromatography, ion chromatography, high performance liquid chromatography, thin layer chromatography and gas chromatography-mass spectrometry. This indicates the wide range of approaches and techniques used to determine the age of written materials. However, all these methods are used mainly during the first two years after writing the document details, which does not allow examining documents that are more than two years old. Methods: Raman spectroscopy was used as the main research method. The object of the study was sheets of white A4 paper with printed text printed on them, produced on a laser printer. The subject of the study was areas of paper free of text, as well as areas of paper under toner. The integrated fluorescence of a paper optical brightener based on stilbene was studied in the wavelength range of 400–500 nm. Also, all objects were studied using optical microscopy. Results: The comparison of peak intensity values averaged over 10 brands over the years made it possible to reveal the following regularities: – the ratio of peaks in the paper spectra from which the toner was removed is greater than in the blank paper spectra, and the difference becomes less noticeable as the age of the paper decreases. The ratio of the intensity of the 330 cm-1 peak to the intensity of the 1603 cm-1 peak: the older the document becomes, the lower the average ratios of these peaks in both the blank paper spectra and in the spectra of paper from which the toner has been removed. –the intensity of the peak in the region of 280 cm-1 and 1 086 cm-1 of the Raman shift increases with decreasing the age of the toner-free paper.– a gradual increase in the intensity of the 380 cm-1 peak is observed when comparing the paper samples from which the toner was removed for 2016, 2018, 2020, and 2022. Regularity was also found in the change in the ratio of the average statistical values of the peak at 280 cm-1 in the spectra of the paper under the toner to a similar peak in the spectra of the paper free from text: the value of this ratio decreases with decreasing the paper age. At the same time, the paper fluorescence signal is an informative parameter that makes it possible to establish some facts from the document’s history. With artificial document aging, a significant broadening of the dispersion region and the appearance of its “splitting” into two or three strata are observed in the distribution of the fluorescence signal level of a paper sheet relative to the average value. The average fluorescence signal of a naturally aged sheet decreases with the age of the document. Conclusion: As a result of research, it has been established that Raman spectroscopy can be successfully used as a method for dating documents. When comparing the degree of degradation of the surface of open areas of paper and areas protected by toner of printed text, different effects of external factors on these areas were established, leading to different rates of degradation processes. The use of Raman peak intensity ratios for paper components in exposed areas compared to peaks under printed text further expands the methodology. The emphasis on spectral methods, in particular fluorescence signal distribution and Raman spectroscopy, to detect surface changes is well justified. It demonstrates a holistic approach to document analysis, taking into account both the chemical changes observed using Raman spectroscopy and the fluorescence signal distribution that may indicate signs of artificial aging through light exposure. This combination of methods appears to be reliable for assessing the age of documents and can make significant contributions to the field of forensic document examination.

Real-time non-destructive monitoring of supported liquid membranes using electrochemical impedance spectroscopy

The degradation of supported liquid membranes (SLMs) due to membrane liquid leaching has been a hurdle for their implementation in resource recovery from waste streams. We present a novel approach utilizing four-electrode mode electrochemical impedance spectroscopy (EIS) for real-time, non-destructive monitoring of SLM degradation, providing detailed analysis of SLM's structural changes. We first showed that SLMs may be depicted as an electrical circuit of resistors and capacitors by EIS. The EIS then revealed that SLM degradation progressed over four different phases as a result of varying rates of thickness and area reduction of the SLM. To demonstrate the effectiveness of EIS-based diagnosis, we prepared SLMs designed for selective medium-chain fatty acid (MCFA) extraction in intact, partially, and completely degraded states, determined by the EIS. The intact SLM showed a high selectivity (∼50) for MCFAs over short-chain fatty acids. The selectivity decreased to ∼22 in the partially degraded SLMs, and less than 1 in the completely degraded SLM, indicating the clear linkage between the degree of degradation and the separation performance. Our four-electrode mode EIS method is expected to serve as a key tool for efficient SLM operation and stable SLM development.

Impaired belief revision yet intact information seeking in positive schizotypy: A modified task of bias against disconfirmatory evidence

Cognitive models of delusions emphasize the role of bias against disconfirmatory evidence (BADE) in maintaining false beliefs, but sources of this tendency remain elusive. While impaired information integration could be an explanation for this tendency, the lack of information seeking motive could also result in disregard for new evidence once a (false) belief is formed. The role of information seeking in the association between psychosis-proneness and belief inflexibility has not been investigated in the context of a social interpretation task. In this study, we modified the Interpretation Inflexibility Task (IIT), which assess bias against disconfirmatory evidence in interpersonal contexts, to permit assessment of information seeking by allowing participants to skip seeing increasingly disambiguating information (in the form of pictures at varying degrees of degradation). A robust regression analysis was conducted to examine whether increasing severity of positive schizotypy is associated with more frequent skipping of later trial stages, to examine information seeking. Controlling for the number of pictures seen by participants, a robust mixed effects analysis was conducted to investigate the associations of positive schizotypy, trait anxiety, and the emotional valence of the scenario with a measure of belief revision. Participants higher in positive schizotypy did not opt out of seeing disambiguating information more frequently, p = 0.65, ß = 0.04; despite this, they still exhibited heightened belief inflexibility by rating the lures and true explanations as equally plausible, p < 0.001, ß = -0.32. These results suggest that bias against disconfirmatory evidence in positive schizotypy is unlikely a result of reduced information seeking, leaving impaired information integration as a more likely source.

Investigating the determinants of marine environmental degradation in Africa: What roles can economy, population, capture and energy play?

This study firstly examines the quality of marine eco-environment in Africa using Tapio decoupling model, and analyzes the sustainability level of the development of “population agglomeration - marine environment - economic growth”. Secondly, a series of econometric tools, such as ARDL, FMOLS, AMG model and DH panel causality test, are used to investigate the long- and short-term impacts of economic growth, population agglomeration, marine capture and energy consumption on the African marine eco-environment, and to analyze the differences between the sub-regions in Africa. The results indicate that: Adebayo and Kirikkaleli (2021) (Adebayo and Kirikkaleli, 2021) the decoupling state of “population-environment” has shifted from expansive negative decoupling to more optimized strong decoupling, and “economy-environment” has gradually changed from strong negative decoupling and expansive negative decoupling to strong decoupling. Ali et al. (2017) (Ali et al., 2017) There existed a bi-directional causal relationship between the degree of marine environment degradation and economic growth, population agglomeration, marine capture and energy consumption. Al-Mulali and Sab (2012) (Al-Mulali and Sab, 2012) In the short term, the economic EKC hypothesis does not hold in North and West Africa, while Central, East and Southern Africa are consistent with the EKC hypothesis. In the long term, the EKC hypothesis is valid in Central, East and Southern Africa, while is not valid in North and West Africa. Overall, reducing population agglomeration levels, marine fishing and energy consumption might mitigate marine environmental degradation in Africa.

Effect of alkali treatment and fungal degradation on the nanostructure and cellulose arrangement in Scots pine cell walls – A neutron and X-ray scattering study

Research on new conservation treatments for historical wood requires considerable amounts of appropriate wood material, which is hard to acquire. Thus, we produced biologically and chemically degraded model wood that could be used as a representative material in future research on consolidating agents. Using chemical composition determinations, we found that fungal decay targeted mainly polysaccharides, while alkaline treatment mostly reduced hemicelluloses and lignin content. X-ray and neutron scattering showed that all decayed samples had increased disorder in microfibril alignment and larger elementary fibril cross-sections, and alkaline-treated samples had much larger elementary fibril spacing compared to those decayed by fungi. These nanoscale and chemical differences correlate with physical property changes. For example, decreased cellulose crystallinity and increased disorder of the microfibrils in degraded cell walls likely contribute to the lower elastic moduli measured for these cell walls. The obtained data improves understanding of how degradation alters wood structures and properties across length scales and will be valuable for future studies focusing on archeological wood. Moreover, it leads to the conclusion that it is more appropriate to develop treatments that consider not only spatial variability and degree of wood degradation but also the corresponding molecular and nanoscale changes in the cell walls.

Characteristics of Vegetation and Soil of Degraded Grasslands and Their Relationships in Xizang

To investigate the characteristics of grassland degradation on a regional scale in Xizang, data on grassland degradation from the second grassland survey of Xizang and 12 vegetation and soil indicators from the National Tibetan Plateau Data Center were collected. Using ArcMap, 10 000 random sample points were selected on raster data （excluding non-grassland, desertification, and salinization data, leaving 7 949 valid sample points）. The multi-value extraction to-point method was applied to extract degradation and indicator data for each sample point. The characteristics of degraded grassland vegetation and soil and their relationships were analyzed in Xizang. Moreover, random forest modeling was conducted to predict the trend of grassland ecosystem changes. The results indicated that： ① The grasslands in Xizang were primarily composed of alpine steppe and alpine meadow types, accounting for 45.83% and 41.15% of the valid sample points, respectively. ② With the intensification of grassland degradation, the number of steppe-type species among the 17 grassland types gradually decreased, and the proportion of steppe dominated by species such as Stipa purpurea and Carex moorcroftii decreased, whereas the proportion of miscellaneous grasses and Dasiphora fruticosa increased. ③ As the degree of degradation increased, vegetation indicators generally showed a declining trend, with soil total nitrogen, total phosphorus, total potassium, and organic carbon decreasing, whereas soil pH and bulk density increased, and soil moisture content was not significant. ④ A positive correlation exists between soil moisture content, total nitrogen, total phosphorus, total potassium, organic carbon, vegetation cover, net primary productivity of vegetation, normalized difference vegetation index, aboveground biomass, and habitat quality. However, there was a negative correlation between pH and soil bulk density, and the correlation coefficients among various indicators decreased with the intensification of degradation. ⑤ The random forest simulation results showed that during the degradation process, the contribution rates of soil bulk density and habitat quality both exceeded 12%, with the model prediction accuracy reaching 78%. The study revealed that grassland degradation in Xizang was closely related to soil bulk density and habitat quality, indicating that higher soil bulk density or lower habitat quality may correspond to more severe grassland degradation. This provides a scientific basis for future grassland conservation and management.

Self-circulating pulse alternating ventilation composting technology: Biotic and abiotic effects of mature compost on humification during food waste composting

Traditional composting technology relies on external additives such as rice husks to optimize the moisture content and permeability of the pile, which increases transportation and economic costs. This study developed a self-circulating pulse alternating ventilation composting technology, which used mature compost as an additive and explored the optimal ratio and strengthening mechanism. Six composting experiments were set up with mature compost as additive and rice husk as control based on the self-made alternating ventilation composting reactor. The results showed that adding 10 % mature compost (wet weight) significantly extended the high-temperature phase (15 days). The total organic carbon degradation degree was 1.10 to 2.11 times higher, and the degree of directional humification was 1.56 to 3.39 times higher than those of the other groups. This may be due to the biological and non-biological effects of the mature compost. On one hand, adding mature compost increased the relative abundance of lignocellulose-degrading functional microbes, which enhanced the metabolic levels of xylanolysis and cellulolysis. On the other hand, it accelerated the dissolution and release of humus precursors, increasing the content of aromatic compounds such as phenyl-β-D-glucoside and indolizine, and thereby accelerating the condensation process. These results demonstrate that self-circulating pulse alternating ventilation composting technology is a low-cost green composting technology with the potential to achieve efficient treatment of food waste.