Decomposition Of Material Research Articles

Cover crops are unlikely to pose a risk to the management of Neopestalotiopsis sp. of strawberry in Florida

An aggressive Neopestalotiopsis sp. has emerged causing leaf spot and fruit rot on strawberry. In Florida strawberry production, cover crops (CCs) are grown in the summer to maintain and enhance soil structure and properties. Although CCs can be used in integrated disease management programs, they could also serve as hosts and increase inoculum levels. Since Pestalotiopsis-like fungi are known for their endophytic ability and wide host range, we sought to determine the effect of CCs commonly used over the summer in Florida on Neopestalotiopsis sp. inoculum. Pathogenicity was tested on sunn hemp, iron clay cowpea, sorghum sudan, oats, sunflower, and ryegrass. Moreover, trials in strawberry fields with histories of disease outbreaks, were conducted using iron clay cowpea, sorghum sudan, and sunn hemp as CCs plus a fallow control. Plants were evaluated for presence of symptoms in the field or following incubation in the laboratory. Soil samples were collected from each treatment and processed using a semiselective medium. Strawberry isolates were pathogenic to all the inoculated CCs, but symptoms were subtle and did not progress over time. Symptoms were not observed on the CCs under field conditions. Neopestalotiopsis sp. was successfully isolated from a single sorghum plant at one trial site, a single clay pea plant at another site, and a single sunflower plant at a third trial site. This suggests that the risk might be more closely associated with the decomposition of strawberry plant material rather than the infection of alternate hosts. Colony-forming units per g soil varied from 0 to 125, and differences were not consistent among trials. Our data suggest that the CCs tested do not pose a risk of increasing pathogen levels on strawberry fields and should still be used to protect and enhance organic matter in the soil.

Mechanisms of Thermal Decomposition in Spent NCM Lithium-Ion Battery Cathode Materials with Carbon Defects and Oxygen Vacancies.

Resource recovery from retired electric vehicle lithium-ion batteries (LIBs) is a key to sustainable supply of technology-critical metals. However, the mainstream pyrometallurgical recycling approach requires high temperature and high energy consumption. Our study proposes a novel mechanochemical processing combined with hydrogen (H2) reduction strategy to accelerate the breakdown of ternary nickel cobalt manganese oxide (NCM) cathode materials at a significantly lower temperature (450 °C). Particle refinement, material amorphization, and internal energy storage are considered critical success factors for the accelerated decomposition of NCM cathode materials. In our proposed approach, NCM cathode materials can develop active sites with carbon defects (Cv) and oxygen vacancies (Ov), which improve the reduction and breakdown of H2. The adsorbed H2 on the surface of NCM decomposes into H* and combines with oxygen to form OH species, which can be facilitated by Ov via the enhanced charge transfer. The introduced Cv can enhance H2 cracking and generate *C-H species to promote the thermal decomposition of NCM. The presence of defects proves to foster the preferential reduction of Mn(IV) by H2, leading to a lower activation energy for the NCM decomposition (from 139 to 110 kJ/mol) with less H2 consumption. Life cycle assessment suggests a reduction of 4.42 kg CO2 eq for the recycling of every 1.0 kg of retired batteries. This study can promote material circularity and minimize the environmental burden of mining technology-critical metals for a low-carbon transition.

IMPROVEMENT OF THE PRODUCT COMPOSITION FROM NITRIC ACID PROCESSING OF KYZYLKUM CARBONATE PHOSPHORITES

The process of producing NP-fertilizers by nitric-sulfuric acid decomposition of phosphate rock (17.20% P2O5) under thickening slurry conditions has been studied. It was shown that the higher the recycle ratio, the lower the moisture content of the final product. Increasing the HNO3 dosage above 30% and H2SO4 above 70% is undesirable, as the product's moisture content exceeds 6.03% and it has increased acidity. To avoid issues during ammoniation, an optimal rate of nitric and sulfuric acid was proposed—73.5-91%, which produced products containing 9.34-10.61% -P2O5total; 3.04-4.54% N; P2O5 digestive:P2O5 total = 73.4-82.3%; pH = 3.3-3.6, and granule strength of 2.1-2.3 MPa. The process of producing NPK-fertilizers was also studied by adding nitrogen components such as K2SO4, KCl, and K2CO3 to the products of complete nitric acid decomposition of washed and dried concentrate (24.10% P2O5) and fine fractions (18.55% P2O5). The process includes decarbonization and decomposition of the phosphate raw material (simultaneously in one apparatus), neutralization to a pH not lower than 3.5, evaporation of the slurry to a density of at least 1750 kg/m3, the addition of potassium salts at N:P2O5:K2O ratios of 1:1:1, 1.5:1:1, and 1:1.5:1, product granulation, drying in the presence of recycle, and cooling.

Natural Self-Purification of Creek Ecosystems: The Role of Foam Formation in Pollutant Absorption and Microbial Decomposition

<p style="text-align:justify;text-indent:36.0pt;"><span style="font-family:"Times New Roman","serif";font-size:12.0pt;line-height:115%;" lang="EN">This study investigates the natural self-purification ability of a creek through the process of froth formation. The research focuses on the creek's capacity to clean itself by capturing and removing pollutants naturally. The problem addressed is the accumulation of organic and inorganic contaminants in the water, which poses a threat to the aquatic ecosystem. The proposed solution explores how naturally formed froth can act as an effective mechanism for trapping and eliminating a wide range of pollutants. The froth formation is driven by biological processes, including the decomposition of organic matter by fungi, bacteria, Archaea, Algae, Virsus, Protozoa and animal parasites. These processes release biological surfactants and biogas microbubbles, which, combined with dissolved air and pollutants, lead to the creation of froth enriched with contaminants. The findings confirm that the creek has a natural ability to purify itself, as the froth effectively absorbs and collects dissolved pollutants. This process reduces the organic load in the water, thereby improving water quality. The study demonstrates that froth formation is a vital subprocess in the self-purification of river ecosystems, particularly through microbial decomposition of organic material. This natural mechanism supports water treatment by enhancing the removal of contaminants. The research validates the hypothesis that the creek's froth formation plays a significant role in its self-cleaning process, offering insights into the potential for natural water purification methods.</span></p>

PEMBERDAYAAN PETERNAK MELALUI PELATIHAN PEMBUATAN PUPUK KOMPOS DESA SOROPIA KECAMATAN SOROPIA KABUPATEN KONAWE

Community service activities integrated with KKN-THEMATIC carried out by the UHO Faculty of Animal Husbandry Lecturer Team took place in Soropia Village, Soropia District, Konawe Regency. Compost is an organic fertilizer produced through the process of decomposition of organic materials, especially animal waste, by active microorganisms such as bacteria and fungi. The purpose of this service is to provide training and technology transfer in making compost. The methods used include delivering materials and demonstrations. In this activity, training in making compost was carried out by utilizing cow dung which is widely available around the Soropia Village settlement, which is then mixed with super decomposer EM4, rice husks, granulated sugar, and water. Through this training, the community is given knowledge about the use of waste from agriculture and livestock to be processed into useful products, especially in the fields of livestock and organic farming which are currently developing in Soropia Village. The farmers showed high enthusiasm during this activity and appreciated the service carried out, with the hope that similar activities can be continued in the future.

Features of the microbiome of burial soils

Introduction. On the territory of the Russian Federation, as well as worldwide, a large amount of space is allocated for burials. The soils found in the burial areas have their own characteristics. In the scientific literature there is a few works devoted to the problem of hygienic assessment of cemeteries from the point of view of their impact on the environment, as well as on the population living next to necrosols or working on them. Depending on the chemical and biological effects, the microbial composition of the soil changes. This process is influenced by many factors, including humidity, the initial content of organic and mineral substances, level of acidity, structure of the soil and peculiarities of the course of intra-soil gas-phase reactions. The key participants in the decomposition of organic material are bacteria and fungi, the diversity and dynamics of which directly depend on the degree of soil contamination with pollutants. The purpose of this study was to analyze the microbiota of cemetery soil in its various layers. Materials and methods. The cemeteries of Moscow (NikoloKhovanskoye, Nikolo-Arkhangelskoye, Perepechenskoye), Moscow (Mytishchenskoye, Domodedovo), Tula (Municipal Cemetery No. 1 of the Municipal State Enterprise of the Municipal Formation of the City of Tula Combine of Specialized Services), Kursk (old city cemetery Kurchatov), Krasnoyarsk (Zheleznogorsk) regions and Altai (Yarovoye) Krais were selected as research objects for assessing the microbiome of soils. Results. The most common bacterial pathogens were found to be Enterococcus spp. (81%), Bacillus spp. (75%) and E. coli (45.1%). Mushrooms of Penicillium spp.. were isolated from 61% of the samples. The revealed microbiota profiles of the samples of the studied cemetery soils reflect the microbial composition of humans, which allows substantiating the main methods and algorithm for identifying decomposition processes depending on the time frame of burials. Limitations. The limitation of the study is due to the risk of contact with cemetery soil was not assessed, since not all genera of isolated microorganisms could be identified by their biochemical properties. Conclusion. Studies conducted in cemetery areas have shown how diverse the soil microbiome is in burial sites and varies depending on the depth of sampling. The microbiota profiles of cemetery soil samples identified during the study reflect the lifetime microbial composition of the human body, which makes it possible to substantiate approaches to identifying decomposition processes depending on the time frame of burials.

Направления совершенствования сероочистки, осушки и переработки природного газа

The results of the work of the staff of the Department of “Chemical Technology of Oil and Gas Refining” of Astrakhan State Technical University in the field of separation of three-phase reservoir mixture, increasing the efficiency of desulfurization, improving the process of drying gas and the production of continuous hydrocarbons – raw materials for petrochemistry. The influence of the quality of raw materials entering processing on the formation of deposits in technological equipment has been studied. Reconstruction of the inlet and three-phase separators of high-pressure reservoir mixture separation plants by installing a vibration damper and a depulsor on the reservoir mixture supply line to the installation, as well as reconstruction of the input of raw materials into the separator of the installation. The use of the KPG-200 defoamer and the KPG-200 AV antifoamer made it possible to reduce the consumption rate of defoaming reagents several times in gas purification plants from acidic components. The influence of various impurities on the foaming of working amine solutions (mechanical impurities, coal dust, products of thermal destruction of amine, thermostable salts, corrosion inhibitors) has been determined. It was revealed that the products of thermal degradation of amine have the greatest effect at concentrations above 3% by weight. A method for reducing the content of mechanical impurities in a solution of diethanolamine in a constant magnetic field has been developed and introduced into an industrial desulfurization plant. The filtration efficiency increases 2.6 times, the foam height is halved, and the foam stability is quadrupled. At the same time, the activity of the defoamer increases by 1.7 times. The mathematical dependence of the height of the protective layer of aluminum oxide in an adsorber with zeolite on impurities of diethanolamine has been experimentally found. The effectiveness of the developed improved distribution ring device is shown, the use of which makes it possible to practically eliminate dead zones in the zeolite layer and thereby increase the efficiency of the adsorption process and increase the inter-regeneration period on the drying unit. Studies of the catalytic pyrolysis of the butane fraction using CVM-type pentasils modified with the introduction of chromium can reduce the process temperature compared with the thermal decomposition of raw materials by more than one hundred degrees 100 °C.

Performance Assessment of Wood-Based Composite Materials Subjected to High Temperatures

This paper is based on research placed within the broader framework of the growing environmental impact requirements of building materials. Given this context, wood-based composite materials have emerged as a promising and innovative solution for structural elements. The current work aims to define a system for testing the mechanical behavior of glued laminated timber elements when exposed to high temperatures, in the neighborhood of the pyrolytic decomposition of materials. These tests monitor the transient behavior of the composite material and characterize the parameters involved in the thermo-mechanical analysis of elements constructed using this type of engineered wood product. The tests are used for the calibration of the material models involved in the numerical analysis and for the analysis of potential prototypes, considering the transient thermal load and heat propagation through the materials. By taking such tests, benchmark models and laboratory procedures are defined that can be used in the future to evaluate different materials, existing or new, and material combinations used to construct such a composite.

Methanothermobacter thermautotrophicus and Alternative Methanogens: Archaea-Based Production.

Methanogenic archaea convert bacterial fermentation intermediates from the decomposition of organic material into methane. This process has relevance in the global carbon cycle and finds application in anthropogenic processes, such as wastewater treatment and anaerobic digestion. Furthermore, methanogenic archaea that utilize hydrogen and carbon dioxide as substrates are being employed as biocatalysts for the biomethanation step of power-to-gas technology. This technology converts hydrogen from water electrolysis and carbon dioxide into renewable natural gas (i.e., methane). The application of methanogenic archaea in bioproduction beyond methane has been demonstrated in only a few instances and is limited to mesophilic species for which genetic engineering tools are available. In this chapter, we discuss recent developments for those existing genetically tractable systems and the inclusion of novel genetic tools for thermophilic methanogenic species. We then give an overview of recombinant bioproduction with mesophilic methanogenic archaea and thermophilic non-methanogenic microbes. This is the basis for discussing putative products with thermophilic methanogenic archaea, specifically the species Methanothermobacter thermautotrophicus. We give estimates of potential conversion efficiencies for those putative products based on a genome-scale metabolic model for M. thermautotrophicus.

Influence of earthworms on the mobility and bioavailability of metals, metalloids and radionuclides in historically contaminated soil

While soil characteristics such as pH, cation exchange capacity and organic matter are known to influence the mobility of pollutants in soil and the transfer to vegetation, far less attention has been paid to the possible non-trophic influence of organisms on pollutant transfer to other species. When pollutants are present in a bound unavailable form in the mineral or organic fraction, they can be made available through bio-weathering and decomposition of organic material. Within this study, the impact of earthworms on the mobility of metal(loid)s and radionuclides in soil and their transfer to vegetation was evaluated and the pathways through which earthworms work were studied. Soil from a Belgian field, historically contaminated with metal(loid)s and radionuclides, was used and microcosm systems were applied to mimic the natural interactions between soil, earthworms (Lumbricus terrestris) and vegetation (Lolium perenne). Metal and radionuclide concentrations were determined in soil, pore water and grass. In addition, soil pH, (chromophoric) dissolved organic matter, the ionic composition of pore water and the soil microbial activity were analysed. In general, earthworm presence significantly increased the concentration of most pollutants in soil pore water. This could be a direct consequence of decreased soil pH and increased humification. The latter also lead to higher nutrient concentrations in pore water that were depleted in the root zone due to high accumulation by plants. Indications were found for earthworm-induced effects on the soil microbial activity. The results show that earthworm activity can increase leaching of metal(loid)s and radionuclides and enhance dispersion into the environment and transfer to other biota and the food chain. Biologically induced release or remobilization of pollutants in the soil should therefore be considered in the context of risk assessment and site management strategies.

Combined use of Bacteria and Enzymes in the Degradation of Polymer Materials

The development of the plastics industry, pro-ecological directives and environmental problems related to the decomposition of biodegradable plastics create necessity to develop a way to properly manage waste from materials that should not be deposited in the environment. A bioproduct has been developed to be used for accelerating the biodegradation of polymer materials. The bioproduct includes carefully selected microorganisms and enzymes. It has been observed that metabolic activity of selected bacteria increases significantly in the presence of plastic material, causing degradative changes. In addition, enzymes were used that also stimulate the decomposition of polymer materials. Impact of bacteria and enzymes on polymer biodegradation was analyzed using different methods: BOD, mass loss, SEM-EDX and FTIR-ATR. Also the effect on plant growth was examined. Five bacterial strains were selected as the active ingredients of the bioproduct, including two bacterial strains from the designated collection and three isolated from environment. Four hydrolytic enzymes have been selected that have the potential to accelerate the decomposition of polymer materials. Keywords: bacteria, enzymes, biodegradation, polymer materials

IMPROVEMENT OF METHODS FOR DECOMPOSING MOLYBDENUM IN INDUSTRIAL PRODUCTS

The study of methods for extracting molybdenum into solutions from industrial ores and concentrates is an important task in the mining and metallurgical industry. Molybdenum (Mo) is used in the production of steel, alloys, electrode materials, and catalysts. The purpose of this work is to increase the efficiency of decomposition of molybdenum-containing materials, reduce production and processing costs, and minimize environmental impact. The tasks include the development of new chemical and metallurgical processes for processing various ores and concentrates, involving their decomposition and the extraction of molybdenum into a solution. Methodology. The study used microwave autoclave decomposition methods and chemical decomposition (acidic and fusion). The composition of the solution was determined using the atomic absorption method. The novelty of the research lies in the use of isolated microwave autoclave decomposition, which combines high efficiency and environmental safety. Results and discussion. The study compared the results obtained by the method of acidic decomposition and fusion in an open system with those from microwave autoclave decomposition in a closed system. Each method has its own advantages and disadvantages. The results of acidic and autoclave decompositions were similar to each other, while the results of fusion showed increased metal contents. The values of decomposition methods for standard copper and molybdenum concentrates showed results of 0.1-2.4%, respectively. The values of acidic (0.8%; 0.98%) and autoclave (0.9%; 1.04%) decompositions for samples from Chirchik and Stepnogorsk concentrates yielded similar results. Conclusion. The results of the decomposition methods of the materials do not differ significantly from each other from a production or industrial point of view. The analysis results can be applied in practice or used as reference values for scientific research.

Transcriptomic and protein analysis of Trametes versicolor interacting with a Hypholoma fasciculare mycelium foraging in soil

The decomposition of large woody material is an important process in forest carbon cycling and nutrient release. Cord-forming saprotrophic basidiomycete fungi create non-resource limited mycelial networks between decomposing branches, logs and tree stumps on the forest floor where colonisation of new resources is often associated with the replacement of incumbent decay communities. To date, antagonism experiments have mostly placed competing fungi in direct contact, while in nature cord-forming saprobes encounter colonised wood as mycelia in a network. Transcriptomic and peptide analyses were conducted on soil-based microcosms were foraging cord-forming Hypholoma fasciculare encountered a wood block colonised by Trametes versicolor. Protein turnover featured strongly for both species and genes putatively involved in secondary metabolite production were identified. H. fasciculare demonstrated an exploitative profile with increased transcription of genes associated with carbohydrate metabolism and RNA and ribosome processing. T. versicolor showed a shift in signalling, energy generation and amino acid metabolism. By identifying genes and proteins putatively involved in this fungal interaction, this work may help guide the discovery of bioactive molecules and mechanisms underpinning community succession.

NiCoCr2O4 as a potential catalyst for the thermal decomposition of ammonium nitrate: a kinetic investigation

The thermal decomposition of high energetic materials plays an important role in their thermal performance. Use of the catalyst is one of the efficient ways improve the thermal performance of the high energetic materials. Therefore, in this work nickel cobalt chromite (NiCoCr2O4) prepared using precipitation approach was utilized as a catalyst for decreasing the thermal decomposition temperature and activation energy of high energetic material ammonium nitrate (AN). The results suggest that AN/NiCoCr2O4 decomposes at lower temperature (240 °C) within a short temperature range (Thermo gravimetry decomposition curve = 180–250 °C). The kinetic study was investigated using Kissinger-Akahira-Sunose (KAS) and Kissinger method (5, 10, and 15 °C min−1 heating rates). The activation energy of AN was reduced from 158.0 to 141.5 kJ mol−1 and decrease in the pre-exponential factor was observed upon addition of NiCoCr2O4. The outcome of the present work can be used to design AN based high energetic formulations containing NiCoCr2O4 catalyst with better thermal decomposition performance.

An Integrated Experimental and Modeling Approach for Assessing High-Temperature Decomposition Kinetics of Explosives.

We present a new integrated experimental and modeling effort that assesses the intrinsic sensitivity of energetic materials based on their reaction rates. The High Explosive Initiation Time (HEIT) experiment has been developed to provide a rapid assessment of the high-temperature reaction kinetics for the chemical decomposition of explosive materials. This effort is supported theoretically by quantum molecular dynamics (QMD) simulations that depict how different explosives can have vastly different adiabatic induction times at the same temperature. In this work, the ranking of explosive initiation properties between the HEIT experiment and QMD simulations is identical for six different energetic materials, even though they contain a variety of functional groups. We have also determined that the Arrhenius kinetics obtained by QMD simulations for homogeneous explosions connect remarkably well with those obtained from much longer duration one-dimensional time-to-explosion (ODTX) measurements. Kinetic Monte Carlo simulations have been developed to model the coupled heat transport and chemistry of the HEIT experiment to explicitly connect the experimental results with the Arrhenius rates for homogeneous explosions. These results confirm that ignition in the HEIT experiment is heterogeneous, where reactions start at the needle wall and propagate inward at a rate controlled by the thermal diffusivity and energy release. Overall, this work provides the first cohesive experimental and first-principles modeling effort to assess reaction kinetics of explosive chemical decomposition in the subshock regime and will be useful in predictive models needed for safety assessments.

Additives Improving the Efficiency of Biogas Production as an Alternative Energy Source—A Review

Additives for anaerobic digestion (AD) can play a significant role in optimizing the process by increasing biogas production, stabilizing the system, and improving digestate quality. The role of additives largely boils down to, among others, enhancing direct interspecies electron transfer (DIET) between microbial communities, resulting in improved syntrophic interactions, adsorption of toxic substances that may inhibit microbial activity, improving microbial activity, and increasing process stability and accelerating the decomposition of complex organic materials, thereby increasing the rate of hydrolysis. Through the aforementioned action, additives can significantly affect AD performance. The function of these materials varies, from enhancing microbial activity to maintaining optimal conditions and protecting the system from inhibitors. The choice of additives should be carefully tailored to the specific needs and conditions of the digester to maximize benefits and ensure sustainability. In light of these considerations, this paper characterizes the most commonly used additives and their combinations based on a comprehensive review of recent scientific publications, including a report on the results of conducted studies. The publication features chapters that describe carbon-based conductive materials, metal oxide nanomaterials, trace metal, and biological additives, including enzymes and microorganisms. It concludes with the chapters summarising reports on various additives and discussing their functional properties, as well as advantages and disadvantages. The presented review is a substantive and concise analysis of the latest knowledge on additives for the AD process. The application of additives in AD is characterized by great potential; hence, the subject matter is very current and future-oriented.

Characteristics of Dissolved Organic Matter as Affected by Decomposition of Different Organic Materials in Alpine Wetland

Dissolved organic matter (DOM) plays a significant role in the nutrient supply, energy flow, and pollutant transportation in the wetland ecosystem. However, little is known about the effect of the decomposition of different organic materials in alpine wetland water on the DOM characteristics. By conducting a 90-day decomposition experiment with the addition of different organic materials (peat soil, yak manure, and plant litter) alone or their combinations into alpine wetland water, we characterized the water DOM using three-dimension excitation-emission matrix spectroscopy. The results showed that the decomposition of organic materials significantly affected the chemical properties, sources, humification degree, and composition of the water DOM. The decomposition increased dissolved organic carbon and dissolved total nitrogen in the water. For most of the water samples, a fluorescence index ranging from 1.4 to 1.7 and a biological index of less than 0.8 may indicate that both autochthonous and allochthonous sources contributed to the water DOM, which may primarily rely on allochthonous sources. UVA (37.55–46.81% of total fluorescent components) and UVC fulvic-like substances (29.91–35.53% of total fluorescent components) dominated the water DOM compositions. Among the treatments, additions of peat soil and yak manure led to the highest and the lowest humification degree of the water DOM, respectively. For the treatment of the combination decomposition of all three organic materials, the yak manure may stimulate microbial activity and facilitate the decomposition of plant litter and peat soil and, therefore, boost the humic-like substances in the water DOM. These findings may help the development of wetland biomass management with the objective of maintaining alpine wetland ecosystem services.

Lignite reduces odour from broiler farms without reducing production performance

An unavoidable consequence of chicken meat production is the generation of substantial quantities of spent litter. This poses several environmental and social challenges, as broiler farms become hotspots for odour emissions. The main source of odour from broiler litter is the microbial decomposition of organic material. Thus, lignite's previously shown capacity to reduce microbial activity in broiler litter was expected to reduce odour emissions from broiler housing. The effect of lignite on odour emission rate (OER) (ou/s) was investigated using dynamic olfactometry over two consecutive summer broiler grow-out cycles in Victoria, Australia, with lignite applied at 3.5 kg/m2. The air quality dispersion model, AERMOD, was used to investigate how lignite's effect on OER influenced the predicted odour dispersion distances and concentrations in the context of various Australian regulatory requirements. Additionally, the effect of lignite on bird production performance was also determined. This study showed that lignite reduced the OER from commercial broiler housing by an average of 56% over both grow-outs. This effect was observed for the duration of the trial. The observed reduction in OER reduced the required separation distances by 44–53% according to the state odour criteria for Victoria, New South Wales, Queensland and South Australia. There were no observed differences in feed conversion ratio, bird live weight or mortality throughout either grow-out. This study demonstrated the capacity of lignite to reduce odour emissions from commercial broiler housing without reducing bird production performance.

Residual effect of biochar on microbial biomass and enzyme activities of soil cultivated with grape varieties: a two -year field assessment

Biochar has received increasing attention as a soil conditioner, being known for its ability to confer numerous benefits to the soil. Derived from the thermal decomposition of organic materials under low levels of oxygen, biochar concentrates essential nutrients and carbon while having low carbon dioxide emissions. Our hypothesis is that biochar applied as a top dressing can improve soil microbial attributes even after two years in a soil cultivated with different grape varieties. To test this hypothesis, we conducted a field experiment using different doses of cashew wood biochar applied to two grape varieties and evaluated its residual effect on microbial biomass and soil enzymatic activities. The design used was a randomized block design, in a 4 x 2 factorial scheme, with five replications: four doses of biochar (0, 5, 10 and 15 ton ha-1) and two grape varieties (Cabernet sauvignon and Malbec). Soil collection was carried out at a depth of 0-20 cm, to evaluate total organic carbon, microbial biomass carbon and soil enzymatic activities. Our findings revealed that the effect of grape varieties on soil biological properties was more pronounced than the biochar dose, indicating that there is a small residual effect of biochar doses after 2 years of application. Overall, our study provides important insights into the residual effect of biochar on soil microbial attributes and is considered an ecologically sustainable alternative, as it solves the problem of waste reuse and provides a disposal that brings benefits to soil properties.

Thermally-assisted magnetization of magnetic composites for enhanced micro actuator performance: a low-cost approach using permanent magnets

A micro actuator based on magnetic composite materials can control its deformation and movement through varying magnetic fields, showcasing significant applications in fields such as soft robotics and biomedicine. However, existing magnetic composite materials still require complex magnetization processes involving sophisticated equipment and demanding external magnetic fields. This paper proposed a low-cost, thermally-assisted magnetization process based on permanent magnets. It was observed that the maximum magnetic induction intensity on the surface of magnetic composites is linearly correlated with the heating temperature. Additionally, magnetically treated materials at elevated temperatures can achieve traditional high-field magnetization effects at lower field strengths. Specifically, we synthesized a magnetic composite with 50%wt NdFeB@PDMS and investigated the conditions of the thermally-assisted magnetization process based on permanent magnets, along with mechanical and magnetic performance characterization methods. Experimental results indicate that below 200 °C, the tensile strength and elastic modulus of the base material increase with rising temperatures, demonstrating a trend of high-temperature hardening. However, when the temperature exceeds 200 °C, the elevated temperature leads to the decomposition of the base material, resulting in a rapid decrease in the tensile strength and elastic modulus of the magnetic composite. Furthermore, high temperatures can disrupt the magnetic domains of the magnetic material, reducing its coercive force and making it more susceptible to external magnetic fields and heat, thereby compromising the stability of the magnetic material. These findings provide new insights into the development of more stable and controllable magnetic composite materials.