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An analytical methodology was developed for the first time in this work enabling the simultaneous enantiomeric separation of the fungicide fenpropidin and its acid metabolite by Capillary Electrophoresis. A dual cyclodextrin system consisting of 4 % (w/v) captisol with 10 mM methyl-beta-cyclodextrin was employed in a 100 mM sodium acetate buffer at pH 4.0. Optimal experimental conditions (temperature 25 degrees C, separation voltage -25 kV, and hydrodynamic injection of 50 mbar x 10 s) allowed the simultaneous separation of the four enantiomers in <10.7 min with resolutions of 3.1 (fenpropidin) and 3.2 (its acid metabolite). Analytical characteristics of the method were evaluated and found adequate for the quantification of both chiral compounds with a linearity range from 0.75 to 70 mg L-1, good accuracy (trueness included 100 % recovery, precision with RSD<6 %), and limits of detection and quantification of 0.25 and 0.75 mg L-1, respectively, for the four enantiomers. No significant differences were found between the concentrations determined and labelled of fenpropidin in a commercial agrochemical formulation. The stability over time (0-42 days) of fenpropidin enantiomers using the commercial agrochemical formulation was evaluated in two sugar beet soils, revealing to be stable at any time in one sample, while in the other a decrease of 45 % was observed after 42 days. Individual and combined toxicity of fenpropidin and its metabolite was determined for the first time for marine organism Vibrio fischeri, demonstrating higher damage caused by parent compound. Synergistics and antagonists' interactions were observed at low and high effects levels of contaminants.

期刊论文 2025-12-01 DOI: 10.1016/j.talanta.2025.128233 ISSN: 0039-9140

Component temperature and emissivity are crucial for understanding plant physiology and urban thermal dynamics. However, existing thermal infrared unmixing methods face challenges in simultaneous retrieval and multicomponent analysis. We propose Thermal Remote sensing Unmixing for Subpixel Temperature and emissivity with the Discrete Anisotropic Radiative Transfer model (TRUST-DART), a gradient-based multi-pixel physical method that simultaneously separates component temperature and emissivity from non-isothermal mixed pixels over urban areas. TRUST-DART utilizes the DART model and requires inputs including at-surface radiance imagery, downwelling sky irradiance, a 3D mock-up with component classification, and standard DART parameters (e.g., spatial resolution and skylight ratio). This method produces maps of component emissivity and temperature. The accuracy of TRUST-DART is evaluated using both vegetation and urban scenes, employing Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images and DART-simulated pseudo-ASTER images. Results show a residual radiance error is approximately 0.05 W/(m2 & sdot;sr). In absence of the co-registration and sensor noise errors, the median residual error of emissivity is approximately 0.02, and the median residual error of temperature is within 1 K. This novel approach significantly advances our ability to analyze thermal properties of urban areas, offering potential breakthroughs in urban environmental monitoring and planning. The source code of TRUSTDART is distributed together with DART (https://dart.omp.eu).

期刊论文 2025-07-01 DOI: 10.1016/j.rse.2025.114738 ISSN: 0034-4257

With the Bulk Jupiter accident, the dynamic separation behavior of solid bulk cargoes in sea transportation, which is different from the usual liquefaction of cargoes, has gradually come to people's attention and is an almost empty field that urgently needs to be researched. In this work, we first conducted vibration table tests for bauxite, replaced bauxite with transparent soil with the same particle size distribution and moisture content, and combined image processing and analysis techniques to complete the detailed visualization of the dynamic separation process. Through the above research, this article reveals the essential characteristics of dynamic separation, including the changing rules of layer-wise water content, pore water pressure, particle motion, and pore water migration. It is concluded that the most apparent feature of the dynamic separation process is the generation of a free liquid surface containing fine particles in the upper layer. The article concludes with a systematic study of the dynamic separation of typical mineral soil. The novel experimental system developed in this study contributes to elucidating the mechanism of dynamic separation of minerals and soil from a precise perspective. [GRAPHICS] .

期刊论文 2025-06-03 DOI: 10.1080/1064119X.2024.2386083 ISSN: 1064-119X

The study explored the long-term efficiency of an integrated electrodialysis-forward osmosis (EDFO) treatment technology for nutrient recovery and its application in irrigating and fertilizing high-value crops. Results showed a stable energy profile with consistent electrical conductivity (EC) trends in both municipal and dairy digestates, highlighting the system's capacity to maintain ionic stability, essential for long-term operation. Fouling resistance was indicated by gradual and minimal declines in current density, reflecting stable performance after three cycles and reducing the need for chemical cleaning. A greenhouse trial assessed the impact of using treated and untreated wastewater for irrigation on plant growth and nutrient dynamics in southern highbush blueberry (Vaccinium corymbosum L. interspecific hybrid). The plants were grown in a soilless potting media and irrigated with a modified Hoagland nutrient solution (control), untreated municipal or dairy digestate, or recovered nutrient water from municipal or dairy digestate treated by the EDFO process. Leaf area and shoot biomass were similar among the treatments, confirming that wastewater irrigation did not adversely affect blueberry growth. Furthermore, pH levels in the potting media were near or within the optimal range for blueberry cultivation (4.5-5.5), while EC exceeded salinity thresholds for the crop (> 2 dS m(-1)) but did not visibly damage the plants, suggesting that salt levels were manageable with periodic freshwater flushing. Mass-spectrometry-based, non-targeted analysis detected significant reductions in organic pollutants across treatment cycles. In particular, pharmaceuticals and pesticides in untreated digestate were reduced by over 90 % post-treatment, affirming the system's efficacy in removing emerging contaminants that could pose risks in agriculture and consumers. Given the favorable nutrient recovery and contaminant removal, the EDFO system offers a sustainable solution for wastewater reuse, enabling nutrient cycling in agricultural systems and reducing freshwater dependence.

期刊论文 2025-06-01 DOI: 10.1016/j.jece.2025.117178 ISSN: 2213-2929

Gels are transversal materials with key applications in multiple scientific and technological sectors, including the preservation of Cultural Heritage that is a fundamental drive for socioeconomic resilience. Recently, the new class of twin-chain (TC) polymer gel networks was developed, using freeze-thaw (FT) cycles on solutions of polyvinyl alcohol (PVA) with two different hydrolysis degree and molar mass. Taking advantage of polymerpolymer phase separation in the pre-gel solutions, a sponge-like, interconnected porosity is templated in the hydrogels during FT, which concurs to boost the cleaning capability of the gels versus soil and aged coatings that jeopardize paintings and other iconic artworks. This review covers the latest developments in this new class of gels, and their use in the conservation of works of art. The TC gels allowed time-effective restoration of masterpieces (paintings by Picasso, Pollock, Lichtenstein), which would have been risky and time-consuming with conventional restoration materials in wet cleaning. The review discusses gelation mechanisms, the partial replacement or decoration of PVA with non-toxic synthetic or bio-based polymers, the counterintuitive role of gels' tortuosity in the cleaning process, and the upload of these gels with nanostructured cleaning fluids (microemulsions, micelles). Overall, the TC PVA hydrogels constitute an advanced tool to preserve Cultural Heritage and transfer it to future generations; moreover, they represent a class of sustainable soft matter materials with potential impact in several fields, spanning from detergency to the cosmetic, pharmaceutical and food industries, tissue engineering, and others.

期刊论文 2025-04-22 DOI: 10.1016/j.polymer.2025.128294 ISSN: 0032-3861

To address problems encountered in current potato harvesting machines in hilly and mountainous areas, such as potato damage, poor adaptability, low operational efficiency, and the inability of traditional harvesters to meet the requirements in these areas, a new potato harvester equipped with excavation and a multi-stage separation conveyor was developed by using design and simulation programs as an innovative way to identify the best operating factors. SolidWorks Software was used to design an excavation and a multi-stage separation conveyor. ANSYS Workbench machine static structure analyzed stress, strain, and deformation. The working process of soil and tuber separation was tested and kinematically analyzed by EDEM-RecurDyn and a 5F01M camera. A field experiment was also conducted on the machine under several factors: working speed (W), excavation depth (D), vibration intensity level (V), and conveyor inclination angle (N). The quadratic regression orthogonal rotating combination experiment tested four factors with five levels. The results of the non-load experiment showed that the lowest ratio of impurities was at the linear speed level (Q3, S5, O3) for the first and second separation conveyor and the side conveyor, respectively. The results of the field experiment showed that the optimal parameters were the working speed of 1.05 m/s, the digging depth of 180 mm, and the vibration force II inclination angle on the screen surface of 22 degrees, which gave the highest potato lifting rate of 98.8%, and the bruising rate was 1.37%. The damage rate was 1.43%, superior to national industry standards. With its exceptional performance, the machine can effectively meet and solve the challenges of harvesting requirements, making it a valuable tool for the industry.

期刊论文 2025-04-01 DOI: 10.25165/j.ijabe.20251802.9164 ISSN: 1934-6344

Developing biobased thermoplastic polyurethane (TPU) from renewable biomass resources is becoming urgent due to resource scarcity and environmental protection requirements. Herein, a chain extender diol (VAN-OH) containing dynamic imine bonds was synthesized using renewable biomass resource vanillin (VAN), then combined with 1,4-butanediol (BDO) in various proportions, and reacted with poly(caprolactone diol) and 4,4 '-diphenylmethane diisocyanate to synthesize degradable biobased TPU (BTPUs) with excellent performance. Fourier transform infrared, 1H NMR, X-ray diffraction, DMA, thermogravimetric analysis, molecular weight, chemical degradation, and mechanical tests systematically investigated the relationships between the polymer chain structure and the performance of BTPUs. The experimental results demonstrated that the high regularity and strong polar bonds (imine and ether) of VAN-OH enhanced the interactions between macromolecular chains and improved the hydrogen bonding combination, crystallinity, and phase separation of BTPUs, thereby exerting significant contributions to their thermomechanical and degradable properties. BVTPU1 with a mole ratio of BDO/VAN-OH = 7.5:2.5 exhibited the best mechanical performance, degradation time was 37.5% shorter, and initial pyrolysis temperature increased by 13.8% compared to BTPU0 without VAN-OH. In addition, BTPUs have shown some biodegradability and environmental friendliness in soil burial experiments under natural conditions.

期刊论文 2025-02-19 DOI: 10.1021/acsapm.4c04087 ISSN: 2637-6105

Saline soil, common in the western China, poses a significant threat to road engineering due to its salt swelling characteristics. Therefore, studying the water-salt migration patterns within saline soil subgrades and developing methods to interrupt this migration are crucial for road safety prevention and control. Based on the utilization of excavated waste soil, a new type of foamed lightweight soil based on saline soil is proposed as a subgrade separation fault in saline soil areas. Using self-developed equipment, we tested internal temperature changes, vertical displacements, and water and salt distribution after freeze-thaw cycles. The objective was to evaluate its salt insulation and swelling suppression capabilities and to explore the microstructure-based mechanisms underlying salt inhibition. Results indicate that under a temperature gradient, water and salt in the saline soil sample migrate upward, accumulating mainly in the middle and upper sections. Notably, the novel foamed lightweight soil separation fault effectively blocks water and salt migration, significantly suppressing salt swelling. Interestingly, a higher soil salt content results in a more pronounced anti-swelling effect. The porous structure of the foamed lightweight soil can not only store salt effectively, but also block salt migration, allowing salt crystallization within the soil, thereby reducing salt swelling damage.

期刊论文 2025-02-01 DOI: 10.16285/j.rsm.2024.0485 ISSN: 1000-7598

The adhesion property of soil on the metal surface was tested by the orthogonal experiment with 4 factors and 3 levels based on piston pull out method. A regression model of adhesion stress and the factors including moisture content(X-1), pressing time(X-2), settling time(X-3) and separation velocity (X-4) was established. The experiment results show that the influence of each factor on adhesion stress is ranked as X- 1 approximate to X (2) approximate to X (3) > X (4) > X- 3 X- 4 , and the adhesion stress shows an 'S' curve with the increase of separation velocity. The DEM parameters of the soil were calibrated based on the test results, and the contact and disturbance state of soil particles during the test were studied by discrete element method (DEM) using JKR model. The simulation tests show that the maximum adhesion stress occurs when the particles are about to separate from the probe surface, and the soil disturbance state is hierarchical.

期刊论文 2025-01-15 DOI: 10.1016/j.powtec.2024.120410 ISSN: 0032-5910

Given the significant damage rate observed during the transportation of current garlic combine harvesters in China, this study aims to design a new garlic combine harvester capable of achieving minimal harvest losses. The designed machine can simultaneously complete operations for garlic digging, clamping transport, seedling-bulb separation, soil cleaning, and fruit collection across two rows. Through the use of theoretical analysis and calculation of garlic harvesting operations, the key parameters of soil-breaking device, clamping transport device, length-limiting cutting device, and soil cleaning conveyor were determined. The BoxBehnken test technique was utilized within Design-Expert software, and orthogonal experiments were conducted with the unit's forward speed, digging depth, and soil-breaking angle as test factors, and the stem cutting rate and bulb damage rate as test indices. The test results showed that when the unit's forward speed, digging depth, and soil-breaking angle were 0.49 m/s, 100 mm, and 20 degrees, respectively, the working parameter combination was the best, and the rate of stem cutting and damage were 95.71% and 3.10%, respectively. The findings from the field experiment and optimization aligned closely. This study can provide reference for the development of mechanized garlic harvesting.

期刊论文 2025-01-01 DOI: 10.4081/jae.2024.1676 ISSN: 1974-7071
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