Search Results (574)

In the dry regions of the Arabian Peninsula, such as Saudi Arabia, rangeland degradation and the decline of pasture species have significantly reduced phytomass production. The scarcity of grazing pastures has led to an expansion of alfalfa-irrigated fields, exacerbating the risk of water shortages. This study is the first to systematically evaluate the adaptability and production potential of Cenchrus ciliaris accessions in the arid environment of Saudi Arabia. The objective of this study is to evaluate the potential of buffelgrass (C. ciliaris) as an alternative to alfalfa in irrigated crop systems for livestock production and to assess its suitability for reintroduction into degraded rangelands to enhance forage production. For this purpose, accessions of C. ciliaris were collected from five different sites in northern Saudi Arabia (Aja, Jameen, Zaitoun, Gaed, and Industrial zone) to select the most vigorous ecotypes to be introduced in the degraded lands and/or to be used as irrigated forage crop. This study shows that under full irrigation (2500-3000 mm year⁻¹), alfalfa can produce 11.9 t ha⁻¹ to 22.6 t ha⁻¹ with a five-year average of 17 t ha⁻¹. However, C. ciliaris can produce 9.3–18.4 t ha⁻¹ with less water consumption than alfalfa (water supply is estimated at 400–500 mm year⁻¹). The average was about 14.1 t ha⁻¹. Our comparative study of these accessions showed that the Aja accession seemed to be the most salt tolerant, whereas the Jameen accession was the most well-developed, productive (18.4 t ha⁻¹), and overgrazing resistant accession (940.3 g plant⁻¹ after 3 cuts). Therefore, the Jameen accession is recommended for rangeland rehabilitation. In terms of chemical composition, C. ciliaris was less protein rich than alfalfa, but this can be compensated for by its high digestibility, estimated by neutral detergent fiber (NDF of 69.6%). This study identifies the Gaed and Jameen accessions as the most productive and grazing resistant, exhibiting drought and salt tolerance, making them suitable for use in irrigated systems to produce high green- and dry-matter yields or for reintroduction to rehabilitate degraded rangelands for rehabilitation purposes. Full article

Orchards are complex agricultural systems with various characteristics that influence crop evapotranspiration (ET_c), such as variety, tree height, planting density, irrigation methods, and inter-row management. The preservation of biodiversity and improvement of soil fertility have become important goals in modern orchard management. Consequently, the traditional approach to weed control between rows, which relies on herbicides and soil mobilization, has gradually been replaced by the use of permanent living mulch (LM). This study explored the potential of a remote sensing (RS)-assisted method to monitor water use and water productivity in apple orchards with permanent mulch. The experimental data were obtained in the Lis Valley Irrigation District, on the Central Coast of Portugal, where the “Maçã de Alcobaça” (Alcobaça apple) is produced. The methodology was applied over three growing seasons (2019–2021), combining ground observations with RS tools, including drone flights and satellite images. The estimation of ET_a followed a modified version of the Food and Agriculture Organization of the United Nations (FAO) single crop coefficient approach, in which the crop coefficient (K_c) was derived from the normalized difference vegetation index (NDVI) calculated from satellite images and incorporated into a daily soil water balance. The average seasonal ET_a (FAO-56) was 824 ± 14 mm, and the water productivity (WP) was 3.99 ± 0.7 kg m⁻³. Good correlations were found between the K_c’s proposed by FAO and the NDVI evolution in the experimental plot, with an R² of 0.75 for the entire growing season. The results from the derived RS-assisted method were compared to the ET_a values obtained from the Mapping Evapotranspiration at High Resolution with Internalized Calibration (METRIC) surface energy balance model, showing a root mean square (RMSE) of ±0.3 mm day⁻¹ and a low bias of 0.6 mm day⁻¹. This study provided insights into mulch management, including cutting intensity, and its role in maintaining the health of the main crop. RS data can be used in this management to adjust cutting schedules, determine K_c, and monitor canopy management practices such as pruning, health monitoring, and irrigation warnings. Full article

As a result of the energy crisis due, among other things, to climate change, most developed countries have taken steps with the main aim—among other things—of increasing the use of green energy sources that do not rely on fuels (including primarily liquid fuels) but use renewable energies. Plant biomass is a versatile substrate that can be used in many areas of the economy and production, but also for the production of various types of fuel. These range from rapeseed oil used as a component of biodiesel or maize starch for ethanol production to typically cellulosic plants such as energy willow, which can be used for direct combustion. The floodplain is home to this type of vegetation. It is characterized by great diversity in terms of geometric dimensions and mechanical and morphological properties. In addition, the location (easy access to water and sunlight) influences its potential energy value. Vegetation, thanks to favorable conditions, can achieve large weight gains in a relatively short period of time. Therefore, its properties should be carefully recognized in order to make more efficient use of energy and operating equipment used during harvesting. This paper presents an analysis of the changes in the elasticity of willow branches over a period of 16 days following harvesting. The changes were analyzed for branches taken from three different shrubs at three different plant height levels during the post-growth period. Based on the measurements carried out, the elastic modulus E of the shoots was estimated. The average modulus of elasticity ranged from about 4500 two days after cutting to about 5500 MPa 16 days after cutting and showed high variability, reaching even CV = 37%, both within a given shrub and depending on the measurement date. The results presented here indicate a high natural variability of mechanical parameters even within the same plant. Full article

A shape memory alloy with the chemical composition Fe-14Mn-6Si-9Cr-5Ni (mass %) was produced by powder metallurgy (PM) from as-blended powders mixed with mechanically alloyed (MA’ed) powder volumes in amounts of 0, 10 and 20. After powder blending, pressing and sintering, the specimens were hot-rolled, spark erosion cut with different configurations and solution-treated between 700 and 1100 °C. After metallographic preparation, structural analyses were performed by X-ray diffraction and microscopic observation performed by optical and scanning electron microscopy (SEM). The analyses revealed the presence of thermal- and stress-induced martensites caused by solution treatment and pre-straining. Due to the relatively low Mn amount, significant quantities of α′ body center cubic martensite were formed during post-solution treatment water cooling. Solution-treated lamellar specimens underwent a training thermomechanical treatment comprising repeated cycles of room temperature bending, heating and sputtered water cooling. By cinematographic analysis, the occurrence of the shape memory effect (SME) was revealed, in spite of the large amount of α′ bcc martensite. Tensile specimens were subjected to room temperature failure tests and pre-straining (up to 4% permanent strain, after loading–unloading). After tensile pre-straining, a diminution of α′ martensite amount was noticed on XRD patterns, which was associated with the formation of internal sub-bands in the substructure of martensite and were observed by high-resolution SEM. These results prove that SME can be obtained in trained PM_MA’ed Fe-14Mn-6Si-9Cr-5Ni specimens in spite of the large amount of thermally induced α′ bcc martensite, the stress-induced formation of which is impeded by the presence of internal sub-bands. Full article

As a famous high-grade cut flower, the ornamental value and the marketability of lilies (Lilium spp.) are restricted by their short vase life in water. Previous reports have shown that silicon (Si) and several preservatives are able to improve the postharvest performance of cut flowers. However, the optimal combination of Si and one selected preservative to improve the vase quality of cut lily flowers was unclear. In this study, therefore, we investigated the synergistic effects of Si and one of five preservatives (water only, CaCl₂, sugar, 8-HQS: 8-hydroxyquinolin sulfate, and CA: citric acid) on the vase quality of cut lily flowers ‘White Siberia’. It was found that a preservative alone (except sugar) could significantly increase the longevity of vase life, delay the water loss rate, and reinforce the antioxidant defense system (i.e., improve total phenols, total flavonoids, and major antioxidant enzymes, as well as reduce ROS-reactive oxygen species accumulation), compared with the cut stems cultured in water only. However, the maximum flowering diameter was not affected. More importantly, these mentioned synergistic effects were more pronounced when the Si was supplemented. The simultaneous use of Si and 8-HQS was the optimal combination for an improved postharvest performance and improved vase quality, among the 10 treatments. Taken together, a composite vase solution using Si and 8-HQS may be a recommended nutrition strategy to enhance the competitiveness of marketed cut lily flowers. Full article

The Bohai oilfield is characterized by severe heterogeneity and high average permeability, leading to a low water flooding recovery efficiency. Polymer flooding only works for a certain heterogeneous reservoir. Therefore, supplementary technologies for further enlarging the swept volume are still necessary. Based on the concept of discontinuous chemical flooding with multi slugs, three chemical systems, which were polymer gel (PG), hydrophobically associating polymer (polymer A), and conventional polymer (polymer B), were selected as the profile control and displacing agents. The optimization design of the discontinuous chemical flooding was investigated by core flooding experiments and displacement equilibrium degree calculation. The gel, polymer A, and polymer B were classified into three levels based on their profile control performance. The degree of displacement equilibrium was defined by considering the sweep conditions and oil displacement efficiency of each layer. The effectiveness of displacement equilibrium degree was validated through a three-core parallel displacement experiment. Additionally, the parallel core displacement experiment optimized the slug size, combination method, and shift timing of chemicals. Finally, a five-core parallel displacement experiment verified the enhanced oil recovery (EOR) performance of discontinuous chemical flooding. The results show that the displacement equilibrium curve exhibited a stepwise change. The efficiency of discontinuous chemical flooding became more significant with the number of layers increasing and heterogeneity intensifying. Under the combination of permeability of 5000/2000/500 mD, the optimal chemical dosage for the chemical discontinuous flooding was a 0.7 pore volume (PV). The optimal combination pattern was the alternation injection in the form of “medium-strong-weak-strong-weak”, achieving a displacement equilibrium degree of 82.3%. The optimal shift timing of chemicals occurred at a water cut of 70%, yielding a displacement equilibrium degree of 87.7%. The five-core parallel displacement experiment demonstrated that discontinuous chemical flooding could get a higher incremental oil recovery of 24.5% compared to continuous chemical flooding, which presented a significantly enhanced oil recovery potential. Full article

In the process of reservoir water flooding development, the characteristics of underground seepage field have changed, resulting in increasingly complex oil–water distribution. The original understanding of reservoir physical property parameters based on the initial stage of development is insufficient to guide reservoir development efforts in the extra-high water cut stage. To deeply investigate the spatio-temporal evolution of heterogeneity in the internal seepage field of layered reservoirs during water flooding development, water–oil displacement experimental simulations were conducted based on layered, normally graded models. By combining CT scanning technology and two-phase seepage theory, the variation patterns of heterogeneity in the seepage field of medium-to-high permeability, normally graded reservoirs were analyzed. The results indicate that the effectiveness of water flooding development is doubly constrained by differences in oil–water seepage capacities and the heterogeneity of the seepage field. During the development process, both the reservoir’s flow capacity and the heterogeneity of the seepage field are in a state of continuous change. Influenced by the extra resistance brought about by multiphase flow, the reservoir’s flow capacity drops to 41.6% of the absolute permeability in the extra-high water cut stage. Based on differences in the variation amplitudes of oil–water-phase permeabilities, changes in the heterogeneity of the internal seepage field of the reservoir can be broadly divided into periods of drastic change and relative stability. During the drastic change stage, the fluctuation amplitude of the water-phase permeability variation coefficient is 114.5 times that of the relative stable phase, while the fluctuation amplitude of the oil-phase permeability variation coefficient is 5.2 times that of the stable stage. This study reveals the dynamic changes in reservoir seepage characteristics during the water injection process, providing guidance for water injection development in layered reservoirs. Full article

The tribological behavior of silicon nitride (Si₃N₄) ceramic with textured patterns under water lubrication was investigated in this paper. Different textured patterns were fabricated using laser surface texturing (LST). Surface wettability was characterized by contact angle. The original surface and textured Si₃N₄ ceramic with triangular patterns presented as hydrophobic. However, the textured Si₃N₄ ceramic with hexagonal patterns presented as hydrophilic. Surface wettability and textured patterns were important factors affecting the friction performance of the Si₃N₄ ceramic. Our results indicated that symmetrical textured patterns were more beneficial for decreasing the coefficient of friction (COF) at lower reciprocating frequencies. In contrast, better surface wettability played a more important role in reducing the COF at higher reciprocating frequencies. The most severe damage observed on the untextured Si₃N₄ ceramic led to a higher wear rate. The symmetrical structure of hexagonal patterns was more conducive to decreasing the wear rate than triangular patterns. However, the Si₃N₄ ceramic with triangular patterns was more suitable for use at high-speed frictions due to better lubrication. The textured patterns had the function of storing lubricants and capturing and cutting debris. Thus, friction performance was improved by introducing textured patterns onto the surface of the Si₃N₄ ceramic. The friction and wear mechanisms are also discussed in this study. Full article

Objective: It is hypothesized that the way nano- and micro-hybrid polymer-based composites are structured and cured impacts the way they respond to aging. Material and methods: A polymer–ceramic interpenetrating network composite (Vita Enamic/VE), an industrially polymerized (Brillinat CriosST/BC), and an in situ light-cured composite with discrete inorganic fillers (Admira Fusion5/AF5) were selected. Specimens (308) were either cut from CAD/CAM blocks (VE/BC) or condensed and cured in white polyoxymethylene molds (AF5) and subjected to four different aging conditions (n = 22): (a) 24 h storage in distilled water at 37 °C; (b) 24 h storage in distilled water at 37 °C followed by thermal cycling for 10,000 cycles 5/55 °C (TC); (c) TC followed by storage in a 75% ethanol–water solution; and (d) TC followed by a 3-week demineralization/remineralization cycling. CAD/CAM samples were also measured dry before the aging process. Three-point bending test, quantitative and qualitative fractography, instrumented indentation test (IIT), SEM, and reliability analyses were used. Uni- and multifactorial ANOVA, Tukey’s post hoc test, and Weibull analysis were performed for statistical analysis. Results: A significant (p < 0.001) and very strong effect of the parameter material was observed (η_P² > 0.9). VE exhibited two to three times higher elastic moduli and hardness parameters compared to BC and AF5, which were comparable. Strength was highest in BC but was accompanied by high beam deformation. The effect of aging was comparatively smaller and was more evident in the IIT parameters than in the flexural strength or modulus. Reliability was high (m > 15) in VE and BC, regardless of aging protocol, while it was significantly reduced in AF5 following aging protocols b-d. Conclusions: TC was the method of artificial aging with a significant impact on the measured parameters, while demineralization/remineralization cycling had little or no impact. Clinical relevance: The degradation of composites occurred irrespective of the structuring and curing method and manifested in a low deterioration in the measured properties. Full article

The demand for clean-cut seafood fillets has led to an increase in fish processing side streams, which are often considered to be low-value waste despite their potential as a source of high-quality proteins. Valorizing these side streams through innovative methods could significantly enhance global food security, reduce environmental impacts, and support circular economy principles. This study evaluates the environmental sustainability of protein recovery from herring, salmon, and cod side streams using pH-shift technology, a method that uses acid or alkaline solubilization followed by isoelectric precipitation to determine its viability as a sustainable alternative to conventional enzymatic hydrolysis. Through a Life Cycle Assessment (LCA), five key environmental impact categories were analyzed: carbon footprint, acidification, freshwater eutrophication, water use, and cumulative energy demand, based on a functional unit of 1 kg of the protein ingredient (80% moisture). The results indicate that sodium hydroxide (NaOH) use is the dominant environmental impact driver across the categories, while energy sourcing also significantly affects outcomes. Compared to conventional fish protein hydrolysate (FPH) production, pH-shift technology achieves substantial reductions in carbon footprint, acidification, and water use, exceeding 95%, highlighting its potential for lower environmental impacts. The sensitivity analyses revealed that renewable energy integration could further enhance sustainability. Conducted at a pilot scale, this study provides crucial insights into optimizing fish side stream processing through pH-shift technology, marking a step toward more sustainable seafood production and reinforcing the value of renewable energy and chemical efficiency in reducing environmental impacts. Future work should address scaling up, valorizing residual fractions, and expanding comparisons with alternative technologies to enhance sustainability and circularity. Full article

Artichoke (Cynara cardunculus L.) is an herbaceous perennial plant from the Mediterranean Basin, cultivated as a poly-annual crop in different countries. Artichoke produces a considerable amount of waste at the end of the harvesting season in the field (5.2 tons/ha/year, DW) and from the industrial processing of fresh-cut products during the harvesting time (800 tons/year). The qualitative and quantitative phenolic profile and inulin content of artichoke samples from the field and industrial processing waste have been investigated after green extraction. The best operative conditions were achieved using the dried biomass extracted with water at 80 °C for 120 min and a matrix-to-solvent ratio of 1:30. The data obtained showed that the concentration of total polyphenols in fresh artichokes followed this order: stems > heads > leaves > outer bracts. Chlorogenic acid and 3,4 di-O-caffeoylquinic acid were the most concentrated caffeoylquinic derivates, whereas luteolin 7-O-malonyglucoside, luteolin 7-O-glucoside and 7-O-rutinoside were the most abundant flavonoids. The artichoke by-products showed high polyphenolic and inulin values, thus representing an important source of health-promoting biomolecules for application in pharmaceutical and cosmeceutical fields. According to the principles of circular economy, the work scheme proposed in this article, the use of waste and its processing into useful products such as nutraceutical supplies could provide a practical and economic opportunity for companies and farmers involved in the cultivation and industrial processing of artichokes. Full article

In view of the deep burial depth, high formation pressure, and presence of top and bottom water in offshore extra-heavy-oil reservoirs, this paper conducts a study on the production performance and flow field variation law of steam huff-and-puff to steam flooding conversion in thick heavy-oil reservoirs based on physical simulation, and analyzes the development effect of the conversion from steam huff-and-puff to steam flooding. On this basis, by comprehensively considering the advantages of gravity-assisted steam flooding and a three-dimensional HHSD well pattern obtained from physical simulation experiments, this paper proposes a well pattern development mode of steam huff-and-puff to composite displacement and drainage, and analyzes the development effect of this well pattern mode using the reservoir numerical simulation method. The research results show that, compared with the planar well pattern of steam huff-and-puff to steam flooding conversion, the adoption of the three-dimensional well pattern can significantly improve the degree of reservoir production and the expansion dynamics of the steam chamber, and mitigate adverse effects such as the increase in water cut caused by top and bottom water on thermal recovery. The composite development of steam huff-and-puff to composite displacement and drainage can be divided into three stages: thermal communication, gravity drainage-assisted steam flooding, and thermal breakthrough erosion and oil washing. The steam chamber presents a development mode of “single-point development–rapid longitudinal expansion–rapid transverse expansion upon reaching the top–polymerization into a sheet”, and simultaneously possesses the oil displacement mechanisms of both steam displacement and gravity drainage. The proposed composite mode of steam huff-and-puff to composite displacement and drainage has guided the implementation of adjustment wells in the Bohai L Oilfield, and the recovery factor has been increased by about 20% compared with the steam huff-and-puff development of the basic well pattern. This study has reference and guiding significance for the efficient thermal recovery development of this oilfield. Full article

The application of dynamic data in biomechanics is crucial; traditional laboratory-level force measurement systems are precise, but they are costly and limited to fixed environments. To address these limitations, empirical evidence supports the widespread adoption of portable force-measuring platforms, with recommendations for their ongoing development and enhancement. Taiyuan University of Technology has collaborated with KunWei Sports Technology Co., Ltd. to develop a portable 3D force measurement system. To validate the reliability of this equipment, 15 male collegiate students were randomly selected to perform four distinct movements: walking, running, CMJ, and side-cutting. The Bertec system served as a reference device alongside the KunWei system to collect the kinetic characteristics of the test movements. The consistency and fitting quality between the two devices were evaluated through t-tests, ICC, and NRMSE. The research results indicated that there were no significant differences in peak force between the KunWei system and the Bertec system across all four movements (p > 0.05). The ICC values for force-time curves were all above 0.98, with NRMSE not exceeding 0.165. The KunWei system exhibited high consistency and reliability under various motion conditions compared to the Bertec system. This system maintains data accuracy, significantly broadens the application scope of force measurement systems, and reduces procurement and maintenance costs. It has been successfully applied in technical support for multiple water sports and winter projects with ideal results achieved. Full article

Soil microorganisms have long been recognized as primary producers of biogenic N₂O in terrestrial ecosystems. Terrestrial plants can contribute to N₂O emissions by transporting N₂O produced in soils, and there is also evidence that plants may serve as direct producers of N₂O. However, to date, direct evidence for N₂O production by plants remains limited. To exclude N₂O emissions resulting from soil-to-plant transport, this study conducted incubation experiments using cut soybean branches and leaves (cSBF) and intact soil cores under an N₂O-free air background. The natural isotopic signatures (δ¹⁵N and δ¹⁸O) and fluxes of N₂O produced by cSBF and soil were compared across different soybean growth stages over two growing seasons. The observed δ¹⁵N and δ¹⁸O values of N₂O from soil ranged from −26.7‰ to −5.3‰ and −24.1‰ to 22.8‰, respectively. In contrast, the values for N₂O produced from cSBF ranged from −4.7‰ to 33.1‰ and from 23.7‰ to 88.8‰, respectively. Notably, N₂O emitted from plants exhibited significantly higher δ¹⁵N and δ¹⁸O values than soil-derived N₂O (p < 0.05). These findings indicate that the pathways and mechanisms of N₂O production and emission in soybean plants differ from those mediated by soil microorganisms and nitrogen transport processes. Additionally, a significantly higher amount of N₂O emission was observed during early growth stages compared to late growth stages (p < 0.01), suggesting that plant N₂O production may be associated with elevated water content and oxygen-limited conditions within plant cells. In addition to the N₂O uptake by plants observed in some literature, the positive relationship between δ¹⁵N values and N₂O fluxes suggests that N₂O could be consumed in plant cells (p < 0.01), with a high consumption rate often associated with a high production rate. The results of this study provide compelling evidence that plants may represent an overlooked source of N₂O in terrestrial ecosystems. Full article

The shallow, thin super-heavy oil reservoir demonstrates certain characteristics, such as shallow reservoir depths, low-formation temperature, and high crude oil viscosity at reservoir temperatures. In the current production process, the central area of P601 is undergoing high-frequency huff and puff operations, facing certain problems such as decreasing production, low recovery rates, and rapid depletion of formation pressure. Through physical simulation experiments, the various elements of HDNS-enhanced oil recovery technology were analyzed. Nitrogen plus an oil-soluble viscosity reducer can improve the thermal recovery and development effect of super-heavy oil. With the addition of the viscosity-reducing slug, the recovery rate of steam flooding was 58.61%, which was 23.32% higher than that of pure steam flooding; after adding the 0.8 PV nitrogen slug, the recovery rate increased to 76.48%. With the increased nitrogen injection dosage, the water breakthrough time was extended, the water cut decreased, and the recovery rate increased. Nitrogen also plays a role in profile control and plugging within the reservoir; this function can effectively increase the heating range, increase steam sweep efficiency, and reduce water cut. So, the synergistic effects of steam, nitrogen, and viscosity-reducing agents are good. This technology enhances the development of shallow-layer heavy oil reservoirs, and subsequent development technologies are being compared and studied to ensure the sustainable development of super-heavy oil reservoirs. Full article