Search Results (8,672)

Background and Objectives: Spinal stenosis, low back pain, and radiating pain to the lower extremities are caused by inflammation of the spinal canal and impaired blood flow around the nerves. Because JOINS tablets are known to have anti-inflammatory, pain-relieving, and blood circulation-enhancing properties, this research was conducted based on the assumption that they could improve spinal stenosis. Materials and Methods: This was a prospective, randomized, single-center, open-label clinical trial with a 6-month follow-up period. A total of 100 patients with lumbar spinal stenosis were randomized into two groups: 50 patients in the test group and 50 patients in the control group. The control group was prescribed the usual spinal stenosis medications (Naproxen, Limaprost, and Pregabalin), while the test group was prescribed JOINS tablets in addition to the usual medications. Results: The severity of low back pain and radiating leg pain was assessed using a Visual Analog Scale. Spinal functional outcomes were assessed using the Oswestry Disability Index (ODI) and Roland-Morris Disability Questionnaire (RMDQ), and quality of life was assessed using the Short Form 36 (SF-36), with division into Physical Component Score (PCS) and Mental Component Score (MCS). At 6 months, the JOINS group showed a greater reduction in low back pain compared with controls (p < 0.001). At all follow-up periods, the functional outcomes did not show statistically significant differences between the test and control groups. Conclusions: The significant reduction in pain suggests that JOINS tablets may be an effective adjunct for pain relief, particularly in patients at high risk of adverse effects from long-term NSAID use. Full article

This study investigates the flow field and temperature field characteristics of a certain type of aerospace tail-thrust clutch friction plate under engagement conditions. A thermo–fluid–solid coupled convective heat transfer model was established based on the velocity distribution of lubricating oil within the groove cavities. The model was applied to analyze the surface temperature distribution of a single friction pair (friction plate and steel plate) under different operating parameters. The results reveal that both the inlet temperature and flow rate of the lubricating oil have a mitigating effect on temperature rise. However, due to the geometric constraints of the groove structure, the maximum wetted area and the actual inflow are inherently limited. Consequently, the temperature evolution during engagement is more significantly influenced by rotational speed and applied pressure. In particular, once these parameters exceed certain critical values, the surface temperature exhibits a sharp increase. Furthermore, the optimization of lubricating flow is constrained by friction materials. A higher flow rate does not necessarily yield greater lubrication benefits; instead, the optimal flow rate solution tailored to the friction pair should be pursued. This work provides theoretical insights into parameter control for aerospace tail-thrust clutches in practical operation. Full article

This study investigates fiber content and orientation in prefabricated slab elements made of ultra-high-performance fiber-reinforced concrete (UHPFRC), using novel non-destructive measurement using a coil’s quality factor, where the coil is put to one side of the specimen only. This allows the analysis of slab specimens of arbitrary size. That then allows an accurate quality control of elements made in the prefabrication industry. This study presents an experimental campaign designed to evaluate the non-destructive principle’s accuracy and practical feasibility. Twenty-five large slab specimens were made in an industrial prefabrication plant using various casting methods to introduce different flow-induced fiber parameters. The slabs were subjected to this non-destructive testing, then destructive bending tests and CT scanning to tie the results together and validate the non-destructive results. The results showed that the coil’s quality factor values correspond well to the distribution (concentration) and orientation of fibers, and the method reliably reveals potential defects of the material and can predict the element’s mechanical properties. Full article

Significant chromite losses to tailings in gravity separation plants arise from both suboptimal separator design and inefficient beneficiation processes, posing major challenges to resource utilization, energy efficiency, and environmental sustainability. These losses are particularly critical because the material, already comminuted to liberation size, is discarded, leading to reduced concentrate yield, wasted energy input, and increased environmental pollution. To address this issue, an industrial-scale custom-designed shaking table was developed and tested to recover marketable-grade chromite concentrate (≥42% Cr₂O₃) from processing plant tailings containing 3.25%–4.25% Cr₂O₃, which had accumulated over years of chromite beneficiation. Experimental results showed that, under optimized operating parameters (320 rpm stroke frequency, 13 mm stroke length, 1° deck slope, 1300 g/L pulp density, 800 kg/h feed rate, and 7 tph wash water flow rate), Cr₂O₃ recovery increased from 8% to 27% for the first and second floor operations and from approximately 17% to 41% for the third and fourth floor operations compared with existing plant performance. The results revealed a strong interdependence between Cr₂O₃ recovery and concentrate grade, both of which are critical indicators of process efficiency. Intermediate particle sizes (−0.250 + 0.150 mm) provided the most favorable balance, yielding high recovery rates without substantially compromising the concentrated grade. Full article

Cement is a widely used construction material, but its high temperature after milling can lead to issues such as gypsum dehydration, cement agglomeration, and increased slump, all of which negatively affect concrete performance. Existing cement heat exchangers have several limitations, such as low efficiency, high energy consumption, and strict processing precision requirements. This study introduces a novel layered-plate heat exchanger and analyzes its cooling performance using ANSYS Fluent 2024 R1 software. The results indicated that increasing the height of the cooling unit group significantly improved cooling efficiency from 7.83% at 1 m to 35.99% at 10 m. When the cooling unit group height was maintained constant, adding fins and increasing the cooling water flow rate were key methods to improve cooling efficiency. At a 10 m height, adopting 100 mm (F-1) and 200 mm (F-2) fin spacings and increasing the cooling water usage of over 90t/h can reduce the temperature of 130 °C cement powder to below 80 °C, with a cooling efficiency exceeding 38.47%. This study offers an effective method for lowering the temperature of freshly milled cement, providing theoretical support for cement manufacturers to effectively address the issue of high-temperature cement. Full article

Biobanks are essential for precision oncology, providing high-quality materials for biomedical research. Liquid biopsy has become a key tool for non-invasive detection of tumor-derived biomarkers, including circulating tumor DNA, proteins, and extracellular vesicles. However, the reliability of these assays critically depends on standardized preanalytical procedures. In this study, we evaluated the impact of two plasma isolation methods—direct centrifugation (DC) and density gradient centrifugation (DGC)—on the overall quality of breast cancer samples collected at the Bruno Boerci Biobank (Maugeri, Italy). Plasma obtained with the two methods was analyzed by spectrometry for hemolysis and lipemia, biochemical analysis for protein and lipoprotein composition, flow cytometry for cellular debris and platelet contamination. Preanalytical nonconformities due to hemolysis, icterus, and lipemia were comparable between methods. However, DGC was associated with a higher platelet contamination and reduced albumin and cholesterol levels. Inter-individual variability was preserved, supporting the robustness of patient-specific molecular signatures, despite absolute discrepancies. This study highlights the pivotal role of the isolation techniques in shaping the quality and overall composition of plasma samples. Harmonized, “fit-for-purpose” biobanking protocols are required to ensure reproducibility of downstream analyses, support biomarker discovery, and ultimately advance the identification of novel therapeutic targets in cancer. Full article

The uneven distribution of airflow on the blade surface of a yaw wind turbine triggers a complex non-constant flow, resulting in turbine flow field operation disorder, which, in turn, affects the structural field. In view of the different degrees of influence of different blade materials on the structural characteristics of a wind turbine, a numerical simulation of the flow field and structural field of the horizontal-axis wind turbine under different yaw conditions is carried out by using the fluid–solid coupling method to quantitatively analyse the degree of influence of the material on the structural characteristics of the wind turbine. The results show that the average velocity of the wake cross-section shows a trend of decreasing, then increasing, and then stabilising at all yaw angles. The larger the yaw angle, the wider is the vortex structure dispersion. As the wake develops downstream, the turbulence intensity is shown to decrease and then increase, and the yaw perturbation exacerbates the turbulence disorder in the wake flow field. Along the wind turbine blade spreading direction, the blade deformation phenomenon is significant. The yaw angle increases, the wind turbine blade deformation increases, and the maximum blade stress first increases and then decreases. At a 15° yaw angle, the airflow on the blade surface is more easily separated, and vortices are formed in the vicinity, which impede the airflow in the boundary layer and lead to a reduction in the velocity in the boundary layer in this region. The minimum deformation and maximum stress of the three materials under a 15° yaw angle indicate that the blades are more capable of resisting external deformation under this condition, so 15° yaw is the best operating condition for the wind turbine. This paper employs different materials to quantitatively analyse the extent to which structural characteristics influence wind turbine performance. The findings from this research can provide valuable insights for optimising wind turbine designs. Full article

A mathematical model was established to describe the sublimation and diffusion of water molecules and their adsorption onto cold traps. This model was used to analyze the combined influence mechanisms of sublimation temperature and ambient pressure on the vapor deposition process of water ice. Tunable Diode Laser Absorption Spectroscopy (TDLAS) was employed to provide real-time feedback on water vapor concentration within the experimental apparatus. Based on this feedback, the sublimation temperature was dynamically adjusted to maintain the concentration dynamically stabilized around the target value. A dedicated apparatus for generating controlled water vapor flow fields and detecting concentration was constructed. The accuracy of both the mathematical model and Finite Element Analysis (FEA) simulations was verified through comparative experiments. Laser triangulation was utilized as a method to detect the thickness of the adsorbed ice film on the sample surface. Leveraging this technique, a water vapor deposition and adsorption verification system was developed. This system was used to test the differences in water adsorption performance across various materials and to measure the correlation between the thickness of the adsorbed/deposited ice film on the samples and both deposition time and sublimation temperature. Full article

Due to its high-temperature resistance, high thermal conductivity, electrical conductivity, excellent chemical stability, and outstanding mechanical and electrochemical properties, graphite has been widely applied in various fields. However, the current production process of high-purity graphite is faced with issues such as high energy consumption and insufficient reduction degree. This study utilized COMSOL Multiphysics 6.0 to couple the electromagnetic field, temperature field, velocity field, and flow field during the purification process of graphite. The dimensionless analysis method is adopted to investigate the influence of parameters such as current intensity, magnetic field frequency and concentration on the reduction degree of graphite feedstock, and the energy consumption in the furnace. Through numerical simulation, the interaction mechanism among various parameters under different parameter combinations is compared and analyzed, and the temperature change and fluid motion state of graphite feedstock during the electromagnetic induction heating process are predicted. When the current is 500 A, the average temperature inside the furnace gradually rises with the increase in the magnetic field frequency. This is because the energy input from induction coil and the energy output due to radiative heat loss gradually reach a dynamic equilibrium state. Furthermore, the average temperature inside the furnace continuously increases with the enhancement of the current, and for every increase of 50 A, the average temperature rises by approximately 200 K. Additionally, through dimensionless analysis, the optimal operating conditions for this induction furnace were determined to be a current intensity of 600 A and a magnetic field frequency of 14 kHz. Under these conditions, the reduction degree of the material reaches 99.69%, which achieves efficient purification and economical energy consumption. This study provides a theoretical basis for the optimization of operating parameters in graphite purification process, which is of great significance for improving production efficiency, reducing energy consumption, and promoting the application of high-purity graphite. Full article

While reducing industrial environmental impacts, it is essential to verify that the perceived improvements do not cause unexpected side effects. In the construction materials sector, certain circular economy practices may potentially increase the exposure from natural radioactivity due to the elevated radionuclide content in processed naturally occurring radioactive material (NORM). This study presents the development of a life cycle impact assessment (LCIA) methodology accounting for NORM impacts in construction material life cycles from cradle to use. The methodology builds upon the LCA-NORM life cycle assessment framework previously established by the research group. The novel contributions include enhancements in (1) the dose units, (2) the use-stage exposure scenario, (3) the inclusion of radionuclide inhalation as an occupational exposure pathway and (4) the revisions of key parameters, including the dose conversion coefficients (DCCs). The updated characterisation factors yielded more conservative values at the use stage (e.g., 7 times higher exposure under pessimistic conditions due to radon inhalation) compared to the previous LCA-NORM outputs. An important advancement is the implementation of the new methodology in a novel custom-developed Python package (i.e., NORMIA) to integrate the custom elementary flows into LCA calculations of the Python library Brightway v.2.5. NORMIA generates characterisation factors that quantify the equivalent stochastic risk for human health and non-human biota per unit radionuclide emission and activity, based on user-defined inputs such as construction material type and density. With this study, a more holistic and accurate assessment of the environmental sustainability of construction materials is targeted. Full article

This article investigates liuli qinglou (琉璃青樓, blue–green glazed pavilions) of medieval China as architectural manifestations of the trans-Eurasian jeweled paradise ideal. Tracing developments from the Northern and Southern Dynasties (420–589 CE) through the Tang dynasty (618–907 CE), it outlines an evolutionary trajectory in representing sacred space: from the use of genuine gemstones in West Asian traditions, through their imitation in glass and glazed ceramics, with applications before the Tang remaining selective and elite, to the ultimate abstraction into symbolic blue–green palettes in the cave murals of Kucha and Dunhuang, where chromatic choices may at times reflect pictorial convention. Integrating textual, archeological, and visual evidence, the study shows how Chinese rulers appropriated imported glazing technologies, together with painted or coated blue–green finishes that simulated liuli effects, not merely for ornamentation but to materially embody Buddhist cosmology and to legitimize imperial authority by creating a terrestrial Buddha land. The pervasive use of qing (青, blue–green) in religious art thus reflects a profound sensory-theological translation, illustrating how Eurasian flows of materials, techniques, and ideas were adapted to shape localized visions of paradise through innovative processes of material and visual transformation. Full article

Vertical axis wind turbines (VAWTs) have significant potential for renewable energy generation, yet their operational efficiency is often limited by reduced aerodynamic performance and difficulties during start-up. This study investigates the effect of passive flow control and material selection on the performance of H-Darrieus VAWT blades, with the aim of identifying design solutions that enhance start-up dynamics and overall efficiency. Two-dimensional numerical simulations were conducted using the Dynamic Mesh method with six degrees of freedom (6DOF) in ANSYS 19.2 Fluent, enabling a time-resolved assessment of rotor behavior under constant wind velocities. Two blade configurations were analyzed: a baseline NACA0012 geometry and a modified profile with inclined cavities on the extrados. In addition, the influence of blade material was examined by comparing 3D-printed resin blades with lighter 3D-printed polycarbonate blades. The results demonstrate that cavity-modified blades provide superior performance compared to the baseline, showing faster acceleration, higher tip speed ratios, and improved power coefficients, particularly at higher wind velocities. Furthermore, polycarbonate blades achieved more efficient energy conversion than resin blades, highlighting the importance of material properties in turbine optimization. These findings confirm that combining passive flow control strategies with advanced lightweight materials can significantly improve the aerodynamic and dynamic performance of VAWTs, offering valuable insights for future experimental validation and prototype development. Full article

The paper describes an installation and procedure for evaluating the velocity profile for the airflow produced by the fan of the cleaning unit of a New Holland wheat combine harvester. The velocity profile is based on measurements taken at 52 points spread over the entire surface of the top and bottom sieves, for different speeds of the fan, different positions of the wind boards and different opening positions of the sieves. The experimental data obtained were graphically represented using the Radial Basis Function (RBF) interpolation model and highlighted that the airflow generated by the fan at the upper screen level, in the longitudinal plane and, especially, in the transverse plane, is distributed unevenly, and depends on the fan rotor speed, the opening of the louvers of the two screens and the arrangement of the two deflectors. The correct adjustment of the cleaning unit and correct evaluation of the air velocity profile over the sieves result in the reduction in grain losses from the upper sieve due to grain flotation, reduction in the content of broken grains in the grain tank due to the reduction in the material flow from the tailing auger as well as reduction in the impurities content of the grain tank due to better separation of the material over the surface of the lower sieve. Full article

Large-scale applications of multi-material manufacturing technology face many challenges. One major issue is how to reuse the mixed powder left after printing. In this study, we propose using an effective structure design to compensate for the performance loss of reused materials, thereby achieving the purpose of reusing premixed waste powder in certain non-critical thermal management applications. Taking Cu and Ni premixture powder as an example, some explorations were then conducted on the feasibility of the proposed concept. The morphological inspection confirms that the powder mixture exhibits satisfactory homogeneity, while the Hall flow rate measurements reveal that its flowability is closer to that of pure Ni. The compression tests show that the fabricated Cu-Ni specimens have good energy absorption, whereas tensile tests reveal their favorable ductility. The numerical analysis indicates that the effect of convection heat transfer is much greater than that of conduction heat transfer. Heat transfer experiments show that the Cu-Ni heat exchanger exhibits comparable performance to pure Cu, with a heat transfer effectiveness deviation of less than 1.3%. Previous results indicate that effective structure design can offset the loss of material properties, allowing premixed powders to be utilized in heat exchanger production as a means of recycling waste powders. Full article

Chlorpyrifos (CHP) is a persistent organophosphate pesticide whose presence in water poses serious ecological and health risks. Here, we report a sustainable adsorbent obtained by high-temperature carbonization of immature walnuts (Juglans regia). The adsorbent’s structure, surface chemistry, and charge properties were comprehensively characterized using FTIR, SEM-EDX, zeta potential measurement, BET analysis, and XPS. The synthesis yielded a mesoporous carbon material with a BET surface area of 303 m² g⁻¹. Its performance in CHP removal was assessed under batch and dynamic conditions. Adsorption followed pseudo-second-order kinetics (k₂ = 0.122 mg min⁻¹ g⁻¹; contact time 0–120 min). Isotherm experiments performed at 20, 25, and 30 °C, with equilibrium data best described by the Langmuir and Sips models, reaching a maximum capacity of 43.2 mg g⁻¹. Thermodynamic analysis indicated a spontaneous and endothermic process. The adsorbent demonstrated selectivity for CHP over chlorpyrifos-oxon (CPO) in binary mixtures, retained its efficiency over at least ten regeneration cycles with ethanol, and removed up to 90% of CHP toxicity, as measured by acetylcholinesterase inhibition. Dynamic filtration confirmed its applicability under flow conditions. These findings demonstrate that the investigated adsorbent is an effective, reusable, and selective adsorbent, offering a low-cost and eco-friendly approach to pesticide removal from contaminated waters. Full article