Search Results (167)

Repurposing mineral processing waste offers both environmental and economic benefits, reducing the disposal burden while enabling mineral resource recovery. A magnetic adsorbent, with an Fe₃O₄ content of 71.0%, collected from waste copper converter slag was utilized to recover gold (Au³⁺) from chloride solution. The adsorbent was separated from the slag samples by crushing, grinding to an average particle size of 30 μm, and magnetic separation. Batch adsorption experiments were performed to evaluate the effects of pH, contact time, chloride concentration, and initial gold concentration on gold uptake amount. The material recovered over 99% of gold from chloride solution under acidic conditions and in the near-neutral pH range. The gold sorption rate was also relatively fast and over 98% recovery was achieved after just 15 min of contact time. Increasing chloride concentration did not influence gold uptake. Parameter studies and spectrometric analyses suggest that chalcocite (Cu₂S) and metallic copper present in magnetite slag reduced the gold chloride complex to metallic gold. These results suggest that converter magnetite slag is a potentially effective sorbent to recover gold from secondary sources due to its selectivity and low cost. Moreover, gold-loaded magnetite slag can be easily separated from the solution by magnetic separation and then recirculated to the smelting stage of copper processing to recover the deposited gold and other precious metals. Overall, this work highlights a pathway to transform waste into opportunity, reinforcing sustainability in mineral processing operations. Full article

This study evaluates the potential of marc, a by-product of clitoria (Clitoria ternatea L.) and borage (Borago officinalis L.) infusions, as a preliminary step toward their subsequent conversion into functional food ingredients. After infusion, the marc was collected and processed by carrier-assisted crushing, aqueous maceration, and subsequent separation into extract and residue fractions. The impact of flower pretreatment by milling and marc matrix modification by inulin and maltodextrin was studied on the physical (dry matter (DM), water activity, color), chemical (total phenolic content (TPC), sum of individual phenolic compounds, and antioxidant capacity), and solubility of the microencapsulated fractions. Inulin-formulated powders derived from intact flowers’ marc were characterized by higher dry matter, decreased water activity, and improved chemical profiles. Under these conditions, clitoria by-products exhibited mean dry matter 94.17 ± 0.20%, water activity 0.301 ± 0.003, TPC 3.285 ± 0.052 mg GAE/g DM, sum of individual phenolic compounds 6.267 ± 0.103 mg/g DM, and ABTS-determined antioxidant capacity 0.100 ± 0.001 mmol Trolox/g DM. For borage by-products under identical conditions, dry matter content (−1.60%), water activity (−12.62%), TPC (−39.82%), sum of individual phenolic compounds (−67.55%), and antioxidant capacity (−65.00%) were lower compared with clitoria by-products. An efficient extraction and stabilization approach can open opportunities for upcycling post-extraction herbal residues into high-value food ingredients. Full article

The Xinqiao Cu-S polymetallic deposit is located in the Tongling ore concentration area of the Middle-Lower Yangtze River metallogenic belt. The orebodies consist of skarn orebodies and stratiform sulfide orebodies, but the genetic link between them remains controversial. In this study, magnetite was used as a proxy to systematically constrain the hydrothermal evolution from the intrusion to the contact zone and further to the stratiform orebodies. A representative drill hole (E603) was logged, and samples were systematically collected from the Jitou pluton outward to the contact zone. Composite samples from the 8–28 m interval were crushed and prepared as resin mounts for integrated TIMA automated mineralogy, BSE textural observation, and in situ LA-ICP-MS trace element analysis. Five types of magnetite (Mt1 to Mt5) were systematically identified. Mt1 occurs as inclusions within feldspar in the quartz monzodiorite. It exhibits typical magmatic magnetite characteristics and contains grid-like ilmenite exsolution, indicating crystallization during the late magmatic stage. Mt2 is distributed in the interstices of magmatic minerals, commonly showing hematitization and replacement of ilmenite exsolution lamellae by titanite. Its trace element geochemistry displays magmatic–hydrothermal transitional features. Mt3–Mt5 in the skarn and stratiform orebodies are paragenetic with retrograde alteration minerals (e.g., epidote, chlorite, and actinolite) and sulfides, and are characterized by low Ti, Al, and V contents and high Mg, Mn, and Sn contents, indicating a hydrothermal origin. From Mt3 to Mt5, (Ti + V) and (Al + Mn) decrease, while Zn and Mn increase, accompanied by a decrease in the (Si + Al)/(Mg + Mn) ratio. This reflects a trend of decreasing fluid temperature and progressively enhanced wall-rock buffering. The Mg-in-magnetite geothermometer yields relatively consistent results for Mt1–Mt3, but anomalously high temperatures for Mt4–Mt5. This suggests that the elevated Mg activity in the fluid, caused by reaction with carbonate wall rocks, can significantly influence the calculated temperatures. Therefore, this geothermometer should be used cautiously for magnetite in the outer skarn zone and interpreted in combination with other temperature constraints. The textures, paragenetic mineral assemblages, and trace element characteristics of magnetite collectively reveal a continuous mineralization process linking the skarn and stratiform orebodies at Xinqiao, providing robust mineralogical and geochemical evidence for the contribution of Yanshanian magmatic–hydrothermal activity to the stratiform mineralization. Full article

Trichocentrum ascendens, commonly known as “cola de rata”, is an orchid traditionally used by Indigenous communities to remove warts and heal wounds and in cultural cleansing rituals (“limpia”). However, additional medicinal uses preserved by the Chinantec people of Oaxaca, Mexico, remain largely undocumented and are at risk of disappearing, as this knowledge is now held by only a few individuals. This study gathered information on the therapeutic applications of T. ascendens in the Chinantla region through semi-structured interviews with key collaborators. Information was collected regarding the socio-demographic profiles of the collaborators, as well as the conditions treated, plant parts used, preparation modes, and doses. The species is used to alleviate headaches, toothaches, stomach pains, menstrual pains, body aches, kidney diseases, and inflammation, as well as to treat cultural diseases known as “mal de orin” and “sangre sucia”. Infusions made from mature or developing leaves, along with topical application of crushed leaves, are the main forms of administration. The traditional knowledge documented here underscores the importance of further research to identify the bioactive compounds in T. ascendens and to evaluate their potential inflammatory and analgesic effect. Such studies could lead to the discovery of new pharmacologically active molecules while preserving valuable traditional knowledge. Full article

This research intends to investigate and analyze the usage of Jordanian oil shale ash (OSA) as a replacement material for ordinary Portland cement and pozzolanic cement in mortar. To start, oil shale was collected from the Wadi Al-Shallala location, crushed, sieved and burned at 800 °C for 24 h. OSA partially replaced the ordinary Portland and pozzolanic cements with ratios of 10%, 20%, and 30%. This research looked into the effect of cement substitution on the standard consistency and hardening time for cement paste. The water contents as well as beginning and final hardening times increased due to the higher replacement ratios of the cements. Also, pozzolanic activity index (PAI) along with scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) testing and mechanical properties (compressive and flexural strengths) of mortar with both types of cement substitution were evaluated. The compressive strength and flexural strength were checked following 3, 7, 14, 28, 56 and 90 days of curing, while (SEM) was conducted just at 28 days old with a 20% replacement ratio in mortar specimens. Results show that 20% OSA substitution for ordinary Portland cement or Pozzolanic cement raises compressive strength and flexural strength, plus provides better morphology. Thus, oil shale is seen as a natural pozzolanic material that increases efficiency in cement mixtures. Full article

Background: Peripheral nerve injury can happen for a variety of causes. Despite major breakthroughs in microsurgery, nerve repair results are not always sufficient. Methods: Thirty-two Wistar albino rats were split into four groups: primary nerve repair (PNR), PNR with vitamin D3 treatment, nerve crush injury (NCI), and NCI with vitamin D3 treatment. In the PNR + D3 and NCI + D3 groups, 1 mcg/kg of vitamin D3 was given intraperitoneally on days 1, 3, 5, and 7 of the 12-week healing period. Electrophysiological measurements were taken prior to the injury. At 12 weeks after damage, a hot plate test was performed to assess acute pain, and the electrophysiological measurements were repeated. Before the rats were sacrificed, biopsy samples from the right sciatic nerve were collected for histopathological evaluation. Results: Post-healing action potential values were not statistically different between the PNR and PNR + D3 groups; however, they were considerably lower in the NCI + D3 group than in the NCI group. The reaction time in the hot plate test was considerably slower in the D3-treated groups compared to the control groups. Histopathology score was substantially higher in the PNR + D3 group as compared to the PNR group, and lower in the NCI + D3 group as compared to the NCI group. Conclusions: Other than improved myelination, vitamin D3 treatment following primary repair of transected nerves produced no statistically significant improvement. Vitamin D3 treatment caused a negative impact on the crush injury, as assessed by the findings of histopathology and electrophysiological measurements. Overall, the results indicate that the efficacy of vitamin D3 treatment may vary depending on the type of injury. Full article

This paper examines the study of an advanced design for a continuously operating fluidized bed reactor applied to sunflower husk torrefaction in a superheated steam environment, which is simulated in a cold model of the reactor. The simulated reactor has a diameter of 0.3 m and contains six vertical baffles installed along the reactor walls, providing loop-like movement of crushed husk particles from the reactor loading point to the reactor biomass unloading point. The residence time of crushed sunflower husk biomass particles in the reactor was studied by introducing colored biomass particles into the bed; these particles had the same mass and size as the undyed material. According to modeling results, replacing superheated steam with room-temperature air in the “cold” model may not lead to significant changes in the hydrodynamics of the fluidized bed or their effect on particle mixing. Experiments were conducted at an air velocity of 0.6 m/s relative to the cross-section of the empty apparatus, which is 3.5-fold greater than the minimum fluidization velocity. Samples were collected at the reactor outlet and dissolved in distilled water. The transparency of the resulting solution was measured using a KFK-3 photometer, and the amount of colored substance in each sample was determined accordingly. The most probable average residence time of biomass particles in the cold model amounted to 6–8 min at a Peclet number of 47. To ensure full operation of the torrefaction reactor under ideal plug-flow conditions, the reactor must be equipped with 24 baffles. The residence time of biomass particles required for optimal operation of the reactor was estimated to 24–32 min, which may be sufficient to produce biochar with a high calorific value, suitable for co-firing with coal. Full article

The Discrete Element Method is widely used in applied mechanics, particularly in situations where material continuity breaks down (fracturing, crushing, friction, granular flow) and classical rheological models fail (phase transition between solid and granular). In this study, the Discrete Element Method was employed to simulate stick–slip cycles, i.e., numerical earthquakes. At 2000 selected, regularly spaced time checkpoints, parameters describing the average state of all particles forming the numerical fault were recorded. These parameters were related to the average velocity of the particles and were treated as the numerical equivalent of (pseudo) Acoustic Emission. The collected datasets were used to train the Random Forest and Deep Learning models that successfully predicted the time to failure. SHapley Additive exPlanations (SHAP) was used to quantify the contribution of individual physical parameters of the particles to the prediction results. The main novelty of this study was the prediction of time to failure for entire event sequences. Using only instantaneous particle velocity statistics and without using information about the history of previous events, coefficients of determination in the range R² = 0.81–0.96 were obtained. Full article

The durability of coral concrete in marine tidal zones is a critical concern due to the coupling effects of impact loads and aggressive ion erosion. This study investigates the dynamic mechanical degradation of Sisal Fiber-Reinforced Coral Aggregate Concrete (SFCAC) under a semi-submerged environment, focusing on the interplay between fiber bridging and corrosion evolution. Split Hopkinson Pressure Bar (SHPB) tests were conducted on specimens with varying fiber dosages (0–6 kg/m³) and erosion durations (0–120 days). Quantitative results indicate that while the addition of sisal fibers had a limited effect on increasing the peak impact-compression strength, it significantly modified the failure characteristics. The dynamic compressive strength exhibited a non-linear trend, peaking at 30 days due to pore filling. However, after 120 days, the strength of the Plain Coral Concrete (SF0) deteriorated to 70.84 MPa, while the 6 kg/m³ fiber-reinforced group (SF6) maintained a higher residual strength of 77.63 MPa. Crucially, although the 6 kg/m³ specimens still suffered crushing failure under high strain rates, the fibers effectively mitigated catastrophic shattering by holding the fragments together, exhibiting superior post-peak energy absorption compared to the pulverized plain matrix. Microscopic analysis (SEM) revealed that although the hydrophilic nature of sisal fibers accelerated ion transport (leading to Friedel’s salt and gypsum formation), their physical bridging effect counteracted the corrosion-induced brittleness. Collectively, these findings provide a theoretical basis for the durability design of SFCAC structures in severe marine splash zones and offer new insights into utilizing sustainable, locally sourced materials for island engineering. Full article

The current method of manually handling or using open-loop automation to deal with abnormal coal lumps on the scraper conveyor is inefficient due to constraints, such as safety concerns and equipment wear. To address inefficiencies in the handling of abnormal coal blocks on scraper conveyors, a reinforcement-learning-based method is proposed. Aiming to address the issue that experimenting on abnormal coal handling by scraper conveyors is expensive, this paper designs a variational Auto-Encoder model with the U-MLP network as its core to simulate the processing environment. In addition, given the sparse characteristics of coal block point cloud data, a deep reinforcement learning model based on the LKDG model is designed to control the crushing equipment when dealing with abnormal coal blocks. Through the point cloud data, images, and other information collected by the fully mechanized mining laboratory before and after abnormal processing of coal blocks, we built a simulation environment for abnormal coal blocks, and trained the LKDG model in the simulation environment. To validate the proposed model, we compared LKDG with baseline models in simulation experiments. The results demonstrate that this method can effectively enhance the efficiency of abnormal coal lump processing without human intervention: LKDG achieved a 10.92% higher average reward compared to existing approaches. In terms of engineering applicability, the trained LKDG delivered excellent performance in laboratory tests conducted in a fully mechanized mining environment, increasing the effective crushing count by 67.11% over conventional automated processing methods. Full article

Screening is a critical link in the separation of gold ores. However, issues such as the agglomeration of material masses and screen aperture blinding often lead to low screening precision and poor desliming performance, severely impacting the efficiency of subsequent crushing processes. To address these challenges, this paper proposes a rigid–flexible coupled screening method for viscous and moist gold ores. The time-frequency response characteristics of the screen surface motion were investigated, the influence of processing capacity and moisture content on screening performance was analyzed, and an industrial performance evaluation of the rigid–flexible coupled screen surface was conducted. Laboratory and industrial test results demonstrate that the rigid–flexible coupled screen surface exhibits a periodic, non-regular waveform with a maximum peak vibration intensity of 14.79 g. Screening efficiency is synergistically inhibited by moisture content and processing capacity. When the ore moisture content is below 3% and the processing capacity ranges from 15 to 22.5 t/(h·m²), the screening efficiency can exceed 85%. Compared with conventional screen surfaces, the implementation of the rigid–flexible coupled screen surface achieved a desliming efficiency of 91%, a maximum processing capacity in the crushing stage of 380 tons per hour, a nearly 12% improvement in the screening efficiency of the closed-circuit checking process for crushed products, and an approximately 8% reduction in the circulating load ratio of the crushing circuit. These enhancements collectively ensure the stable operation of both the screening and crushing processes. Full article

Background/Objectives: Early diagnosis and surgical intervention are critical in upper extremity (UE) compartment syndrome to prevent irreversible muscle necrosis or amputation. Despite its prevalence, there remains limited literature guiding surgical management or predictors of complications. This study aims to characterize risk factors and outcomes following UE fasciotomies. Methods: A 14-year (2010–2024) retrospective review was conducted of adult patients undergoing fasciotomies for UE compartment syndrome at a level 1 trauma center. Exclusion criteria included age <18 years, incomplete records, or fasciotomies not performed for compartment syndrome. Data collected include demographics, injury mechanism, presenting symptoms, and diagnostic methods. Intraoperative details obtained include incision type, number of interventions, closure method, presence of muscle necrosis, and amputation. Results: Fifty-five patients (58 extremities) met the inclusion criteria (median age 42 years; 85% male). Mechanisms included fractures (29.3%), prolonged pressure (“found-down”) (25.9%), vascular injuries (13.8%), ballistic trauma (8.6%), crush (6.9%), and other (15.5%). Common symptoms were pain (72.4%), paresthesias (48.3%), and motor dysfunction (43.1%). Isolated fasciotomy incisions included volar forearm (41.4%), hand (8.6%), dorsal forearm (3.4%), and upper arm (1.7%), with the remaining being combinations thereof. Among the 40 total volar forearm fasciotomies, none developed postoperative dorsal forearm muscle necrosis. Muscle necrosis (19%) was associated with pallor (p = 0.05) and pulselessness (p < 0.001). A prolonged pressure mechanism was associated with increased muscle necrosis (p = 0.02) and amputation (p < 0.001). Meanwhile, the fracture mechanism was associated with decreased muscle necrosis (p < 0.001) and higher DPC rates (p < 0.001). Conclusions: Pain, paresthesias, and motor dysfunction were most common symptoms in UE compartment syndrome; pallor and pulselessness correlated with muscle necrosis, indicating advanced compartment syndrome. The prolonged pressure mechanism was associated with greater muscle necrosis and amputation, while fracture-related mechanisms were associated with decreased muscle necrosis and higher DPC rates. Full article

To address the issues of low efficiency and repeated soil compaction caused by segregated pre-sowing operations for residual film recovery and soil preparation in Xinjiang’s long-term film-mulched cotton fields, this study developed a sowing-layer residual film recovery machine integrated with soil preparation functionality. The modular machine sequentially performs harrowing, film-pickup, removal, collection, soil crushing, and leveling operations. An orthogonal experiment focusing on film-pickup rate and film-removal rate was conducted using forward speed, roller speed, and working depth as experimental factors to evaluate the residual film recovery performance. Simultaneously, the effectiveness of the soil preparation operation was quantitatively validated. The results indicated that the order of factor influence significance on the film-pickup rate was forward speed > working depth > rotational speed of the film-removal roller, while the film-removal rate was primarily affected by the rotational speed of the film-removal roller. The optimal parameter combination was identified as a forward speed of 4 km/h, a film-removal roller speed at 300 r/min, and a working depth of 120 mm. Validation tests under these conditions yielded a pickup rate of 71.23% and a removal rate of 95.06%. Regarding soil preparation, the surface evenness was maintained at 1.23 cm after operation, demonstrating significant performance improvement over previous machine prototypes. This study promises to deliver crucial advancements for combined pre-sowing operations, offering support for future agricultural machinery innovation. Full article

Following the Itaewon Halloween Crowd Crush of 29 October 2022, this study examines how public sentiment evolved on Naver, South Korea’s most influential digital platform. While prior research has focused on mainstream media and global social networks, little is known about localized discourse on Naver. To address this gap, we analyzed 2107 user-generated posts collected via Python-based web scraping across three time periods: the immediate aftermath, first anniversary, and passage of the Itaewon Special Law. Semantic network analysis, sentiment classification, and logistic regression were applied to uncover patterns in discourse and emotional tone. Results reveal a shift from grief and outrage in 2022 to demands for political accountability, safety reform, and memorialization by 2024. High-frequency keywords reflected media and government narratives, while low-frequency terms exposed grassroots voices and emotional nuance. Regression analysis confirmed statistically significant associations between sentiment, title length, and year. These findings suggest that digital platforms not only mirror public sentiment but also shape the emotional and political framing of national tragedies. By tracing sentiment over time, this study contributes to understanding how echo chambers, narrative framing, and temporal context interact in shaping collective responses to crisis. Full article

To address the inefficient use of pruned grape branches and the high cost of orchard management, an integrated machine for collecting and crushing grape branches was developed, tailored to the distinctive viticulture methods in Xinjiang, China, and the physical properties of the branches. Based on a unified design scheme, the structural parameters of the collection mechanism and the suitable operating width were optimized through systematic theoretical analysis. The crushing unit was designed with attention to blade shape, quantity, and spatial distribution, while critical operational parameters—including blade dimensions, speed range, and key factors influencing crushing quality—were identified using kinetic analysis. A three-factor, three-level response surface experiment was designed via Design Expert software, incorporating crushing roller speed, pickup roller speed, and ground clearance of the pickup device as test variables. Pickup rate and acceptable fragment ratio were employed as evaluation indicators. Field tests showed that at a crushing roller speed of 2185 r/min, pickup roller speed of 105 r/min, and ground clearance of 10 mm, the pickup rate was 95.93% and the qualified fragmentation rate reached 97.19%, the machine met the operational requirements of achieving over 95% efficiency for both collection and crushing. This study provides a theoretical foundation and technical support for the mechanized treatment of pruned grape branches in Xinjiang. Full article