Search Results (53)

The present study deals with the fabrication of activated carbon from longan peels (LPAC) using a phosphoric acid (H₃PO₄) activation method and an evaluation of LPAC’s capability for the adsorption of Reactive Black 5 (RB5) dye from aqueous solutions. The synthesized LPAC was characterized using XRD, SEM, FT-IR, and EDX, confirming a porous, carbon-rich structure with the dominant elemental composition of carbon (85.21%) and oxygen (12.43%), and a surface area of 1202.38 m²/g. Batch adsorption experiments revealed that optimal performance was achieved at pH 3.0, with equilibrium reached after 240 min. The experimental data were well fitted to the Elovich model p, suggesting a heterogeneous adsorption process with diffusion limitations. The intraparticle diffusion model further supported a multi-stage mechanism involving both film diffusion and intraparticle transport. Isotherm studies conducted at varying temperatures (293–323 K) showed a maximum adsorption capacity exceeding 370 mg/g. The adsorption data fit best with the Freundlich (R² = 0.962) and Temkin (R² = 0.970) models, indicating multilayer adsorption on a heterogeneous surface. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic, with ΔG° values ranging from −23.15 to −26.88 kJ/mol, ΔH° = 14.23 kJ/mol, and ΔS° = 0.127 kJ/mol×K, consistent with physisorption as the dominant mechanism. Predictive modeling using an artificial neural network (ANN) achieved superior accuracy (R² = 0.989 for RRE; R² = 0.991 for q) compared to multiple linear regression (MLR). Calculation from ANN indicated that pH and contact time were the most influential factors for RB5 removal efficiency, while initial dye concentration and temperature were most critical for adsorption capacity. Furthermore, LPAC demonstrated excellent reusability, retaining over 83% removal efficiency after five adsorption–desorption cycles. These findings confirm that LPAC is an efficient and renewable adsorbent for the treatment of RB5 dye in wastewater treatment applications. Full article

This study presents a black phosphorus-based surface plasmon resonance (SPR) biosensor for malaria detection, integrating silicon nitride (Si₃N₄) and single-stranded DNA (ssDNA) to enhance sensitivity and molecular recognition. The biosensor configurations were optimized through numerical simulations, evaluating metal thickness, dielectric layer thickness, and the number of black phosphorus layers to achieve maximum performance. The optimized system (Opt-Sys₄) exhibited high sensitivity (464.4°/RIU for early-stage malaria) and improved detection accuracy, outperforming conventional SPR sensors. Performance was assessed across malaria progression stages, demonstrating a clear resonance shift, increased attenuation, and enhanced biomolecular interactions. Key metrics, including the figure of merit, limit of detection, and comprehensive sensitivity factor, confirmed the sensor’s superior performance. Comparative analysis against state-of-the-art SPR biosensors further validated their capability for highly sensitive and specific malaria detection. These findings establish a promising plasmonic biosensing platform for early malaria diagnosis, potentially improving disease management in resource-limited settings. Full article

This study explored the effect of the combined application of chemical and organic fertilizers on phosphorus morphology and its conversion to an active state. A long-term field positioning experiment comprising five treatments was conducted in black soil. The results concluded that the soil total phosphorus (TP), available phosphorus (AP), inorganic phosphorus, and organic phosphorus contents of all treatments ranked as follows: 1.5M1NPK > M2NPK > M1NPK > NPK > CK. The long-term application of chemical and organic fertilizers increased the proportion of soil reactive phosphorus and moderately reactive phosphorus but decreased the proportion of mildly active phosphorus and residual phosphorus. A phosphorus-31 nuclear magnetic resonance (³¹P NMR) spectral analysis showed that the contents of orthophosphate, pyrophosphate, phosphoric acid diesters, and orthophosphate acid monoesters increased with the application of chemical and organic fertilizers, of which 1.5M1NPK usually resulted in the highest increases. In conclusion, the long-term application of chemical fertilizers could promote the conversion of soil phosphorus into active phosphorus and improve the effectiveness of soil phosphorus, and the long-term use of organic and chemical fertilizers was more effective than the use of chemical fertilizers only, with 1.5M1NPK providing the best effects. Full article

Black bloom is a very serious water pollution phenomenon in eutrophic lakes, with Fe(II) and S(−II) being the key limiting factors for this problem. In this paper, three different machine learning methods, namely, Random Forest (RF), Gaussian Mixture Model (GMM), and Bayesian Network (BN), were used to explore the complex interactions among Fe(II), S(−II), and other aquatic factors in the estuary of Chaohu Lake to better characterize and monitor water degradation by black bloom. The results of RF showed that total nitrogen (TN), ammonia, total phosphorous (TP), suspended sediment concentration (SSC), and oxidation–reduction potential (ORP), which were chosen from 11 factors, had the most important relationships with Fe(II) and S(−II). The 69 sampling sites were divided in three groups identified as worst, worse, and bad according to the observed values of seven factors using the GMM. Then, the BN model was applied to three observation groups. The results showed that the structures of the interaction networks were different between the groups. S(−II) controlled only SSC production in the bad and worse group sites, while SSC was determined by both S(−II) and Fe(II) in the worst group. Ammonia and TN exhibited the most direct importance for S(−II) and Fe(II) production in all observation groups. According to the indications from the BNs, potential management strategies for different water pollution conditions were developed. Finally, the threshold values of Fe(II), S(−II), TP, ammonia, TN, SSC, and ORP, which were 0.80 mg/L, 0.04 mg/L, 0.45 mg/L, 3.44 mg/L, 4.15 mg/L, 55 mg/L, and 135 mv, respectively, were determined on the basis of the BN models. These values will be helpful to develop accurate strategies of oxygenation to quickly eliminate black bloom in the lake. Full article

Black phosphorous (BP) is a novel composite material. Its carrier mobility can reach more than 1000 cm²·V⁻¹·s⁻¹ and has a direct bandgap adjustable from 0.3 to 1.5 eV with thickness, so its photovoltaic performance is good. These properties show great potential for applications in many fields, such as energy storage, sensors, biomedicine, and environmental treatment. With the deepening of research, it is found that the instability of BP under natural environmental conditions and the limitations of its preparation limit its development, while combining with other materials can further optimize its performance, which not only improves the mechanical properties of the material but also gives it new functions. Based on this, this paper summarizes the preparation and optical properties of highly stable metals and their compounds/BP-based nanomaterials in recent years, highlights the progress of their application in photocatalytic hydrogen evolution, and gives an outlook on the challenges and opportunities for the future development of BP in photocatalysis. Full article

Severe musculoskeletal disease characterized by marked joint laxity was the cause of euthanasia in two wild juvenile American black bears (Ursus americanus) admitted to a rehabilitation facility in eastern Tennessee in 2023. Previously, almost all reported musculoskeletal diseases in this population were of traumatic etiology, even in malnourished yearlings. Case 1 was an orphaned 11-month-old male cub exhibiting disproportionate dwarfism, progressive immobility, and joint laxity. Necropsy findings suggested either chondrodysplasia or rickets, and imaging findings supported a skeletal dysplasia. Case 2 was a 14-month-old emaciated male yearling exhibiting joint laxity and immobility. Necropsy findings showed osteoporosis and serous atrophy of fat, and imaging findings were inconsistent with a skeletal dysplasia. Both cases were clinically inconsistent with rickets based on normal calcium, phosphorous, and parathyroid hormone concentrations; however, Case 1 had hypovitaminosis D (9 nmol/L) compared to healthy juvenile black bears. We hypothesize that Case 1 had a genetic chondrodysplasia while the osteoporosis of Case 2 was due to chronic malnutrition. The goal of this case report is to inform wildlife agencies and facilities to monitor for similar, non-trauma-related debilitating musculoskeletal disease in free-ranging bears and evaluate cases that allow us to further understand the disease processes involved. Full article

Recycling spent lithium-ion batteries (LIBs) is crucial to prevent environmental pollution and recover valuable metals. Traditional methods for recycling spent LIBs include hydrometallurgy and pyrometallurgy. Among these methods, solvent extraction can selectively extract valuable metals in spent LIB leachate. Meanwhile, spent LIBs that underwent pyrometallurgical treatment generate a so-called ‘black alloy’ of Ni, Co, Cu, and so on. These elements in the black alloy need to be separated by solvent extraction and there have been few studies on extracting valuable metals from black alloy. Therefore, it is necessary to examine the extraction behavior of elements in black alloy and optimize the solvent extraction process to recover valuable metals. In this paper, four types of organic extractants are used to extract metals from simulated black alloy leachate: di-(2ethylhexyl) phosphoric acid (D2EHPA), bis-(2,4,4-trimethylpentyl) phosphinic acid (Cyanex272), 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC88A), and neodecanoic acid (Versatic acid 10). Based on the pH isotherms, D2EHPA would be the most reasonable for Mn extraction and impurity removal. Cyanex 272 would be more suitable for Co separation than PC88A, and Versatic acid 10 is preferred for Cu extraction over other metals. In conclusion, the optimal combination of extractants is suggested for the recovery of valuable metals. Full article

Entomocomposting is fast and environmentally friendly, boosts soil quality and crop production, and improves resilience to climate change. The black soldier fly larvae (BSFL) catalyze the composting process, but their efficiency is highly influenced by environmental factors and the quality of the substrate. This study employs response surface methodology to discern physical–chemical factors that influence the nutrient quality of BSF frass fertilizer. Internet of Things (IoT) sensors were deployed to monitor in real-time both independent variables (air temperature, moisture content, humidity, and substrate temperature) and dependent variables (nitrogen, phosphorous, and potassium); the data were relayed to the cloud. A non-linear regression model was used to study the relationship between the dependent and independent variables. Results showed that air humidity and air temperature did not have a significant effect on nitrogen and phosphorus accumulation in frass fertilizer, respectively, but phosphorus was significantly influenced by air humidity. On the other hand, neither air temperature nor moisture content has a significant effect on potassium concentration in frass fertilizer. We found that an air temperature of 30 °C and 41.5 °C, substrate temperature of 32.5 °C and 35 °C, moisture content between 70 and 80%, and relative humidity beyond 38% can be conducive for the production of high-quality BSF frass fertilizer. Model validation results showed better robustness of prediction with $R^2$ values of 63–77%, and $R_{\mathrm{adj}}^2$ values of 62–76% for nitrogen, phosphorous, and potassium. Our findings highlight the potential for the application of digital tools as a fast and cost-effective decision support system to optimize insect farming for the production of high-quality frass fertilizer for use in sustainable agriculture and crop production. Full article

What is reported here is an advanced anti-counterfeiting ink whose luminous effect changes over time and at different excitation wavelengths. Unlike traditional anti-counterfeit fluorescent materials, the phosphors used here exhibit multicolor emissions under multiple excitation modes. In this work, the most important building blocks are three classic phosphors with primary colors, red (Ca₂YNbO₆:0.4Eu³⁺), green (SrAl₂O₄:0.01Eu²⁺, 0.02Dy³⁺) and blue (CaAl₂O₄:0.012Eu²⁺, 0.06Nd³⁺, 0.036Gd³⁺), which were synthesized using the high-temperature solid-state method. The phosphors formed homogeneous solid solutions and were uniformly distributed throughout the mixture. A homogeneous transparent luminescent ink was obtained by blending the multi-mode phosphors with transparent screen-printing ink, resulting in multi-mode luminescence by simply varying the proportions of the red (R), green (G) and blue (B) phosphors. Thanks to this simple process, an advanced anti-counterfeiting ink with low production costs was achieved. Anti-counterfeiting logos of a “Giraffe” and “Steam Train” were printed using the transparent fluorescent ink onto black cardstock, exhibiting the characteristic of dynamic luminescence dependent on the duration and excitation wavelength. The anti-counterfeiting effect of the patterns suggests that the fluorescent ink is worth developing and is reliable in its application. Full article

Nutrient-dense, acceptable foods are needed in low-resource settings. Rice bran, a global staple byproduct of white rice processing, is rich in amino acids, fibers, and vitamins, when compared to other cereal brans. This pilot study examines the nutritional contribution of rice bran to the daily diets of mother–child pairs in rural southwest Guatemala. Thirty households were screened. Mothers (≥18 years) and children (6 to 24 months) completed 24 h dietary recalls at baseline and after 12 weeks (endline) for diet intake and diversity analyses. During biweekly visits for 12 weeks, households with <5 members received 14 packets containing 60 g of heat-stabilized rice bran, and those with ≥5 members received 28 packets. The macro- and micro-nutrient contributions of rice bran and whole, cooked black beans were included in dietary simulation models with average intakes established between the recalls and for comparison with dietary reference intakes (DRIs). A baseline child food frequency questionnaire was administered. The 27 mothers and 23 children with complete recalls were included in analyses. Daily maternal consumption of 10 g/d of rice bran plus 100 g/d of black beans resulted in all achieving at least 50% of the fiber, protein, magnesium, niacin, potassium, and thiamin DRIs. Daily child consumption of 3 g/d of rice bran plus 10 g/d of black beans resulted in all achieving at least 50% of the magnesium, niacin, phosphorous, and thiamine DRIs. For 15/17 food categories, male children had a higher intake frequency, notably for animal-source foods and coffee. Dietary rice bran coupled with black beans could improve nutritional adequacy, especially for fiber and key micro-nutrients, with broader implications for addressing maternal and child malnutrition in low-resource settings. Full article

Most 2D materials are unstable under ambient conditions. Assembly of van der Waals heterostructures in the inert atmosphere of the glove box with ex situ lithography partially solves the problem of device fabrication out of unstable materials. In our paper, we demonstrate an approach to the next-generation inert-atmosphere (nitrogen, <20 ppm oxygen content) fabrication setup, including optical contact mask lithography with a 2 $\mathsf{\mu }$m resolution, metal evaporation, lift-off and placement of the sample to the cryostat for electric measurements in the same inert atmosphere environment. We consider basic construction principles, budget considerations, and showcase the fabrication and subsequent degradation of black-phosphorous-based structures within weeks. The proposed solutions are surprisingly compact and inexpensive, making them feasible for implementation in numerous 2D materials laboratories. Full article

The recalcitrant nature of emerging contaminants (ECs) in aquatic environments necessitates the development of effective strategies for their remediation, given the considerable impacts they pose on both human health and the delicate balance of the ecosystem. Semiconductor-based photocatalytic technology is recognized for its dual benefits in effectively addressing both ECs and energy-related challenges simultaneously. Among the plethora of photocatalysts, black phosphorus (BP) stands as a promising nonmetallic candidate, offering a host of advantages including its tunable direct band gap, broad-spectrum light absorption capabilities, and exceptional charge mobility. Nevertheless, pristine BP frequently underperforms, primarily due to issues related to its limited ambient stability and the rapid recombination of photogenerated electron–hole pairs. To overcome these challenges, substantial research efforts have been devoted to the creation of BP-based photocatalysts in recent years. However, there is a noticeable absence of reviews regarding the advancement of BP-based materials for the degradation of ECs in aqueous solutions. Therefore, to fill this gap, a comprehensive review is undertaken. In this review, we first present an in-depth examination of the fabrication processes for bulk BP and BP nanosheets (BPNS). The review conducts a thorough analysis and comparison of the merits and limitations inherent in each method, thereby delineating the most auspicious avenues for future research. Then, in line with the pathways followed by photogenerated electron–hole pairs at the interface, BP-based photocatalysts are systematically categorized into heterojunctions (Type I, Type II, Z-scheme, and S-scheme) and hybrids, and their photocatalytic performances against various ECs and the corresponding degradation mechanisms are comprehensively summarized. Finally, this review presents personal insights into the prospective avenues for advancing the field of BP-based photocatalysts for ECs remediation. Full article

Superconductivity in highly pressurized hydrides has become the primary direction for the exploration of the fundamental upper limit of the superconducting transition temperature, $T_c$, after Drozdov et al. (Nature 2015, 525, 73) discovered a superconducting state with $T_c=203K$ in highly compressed sulfur hydride. To date, several dozen high-temperature superconducting polyhydrides have been discovered and, in addition, it was recently reported that highly compressed titanium and scandium exhibit record-high $T_c$ (up to 36 K). This exceeded the $T_c=9.2K$ value of niobium many times over, which was the record-high $T_c$ ambient pressure metallic superconductor. Here, we analyzed the experimental data for the recently discovered high-pressure superconductors (which exhibit high transition temperatures within their classes): elemental titanium (Zhang et al., Nature Communications 2022; Liu et al., Phys. Rev. B 2022), ${TaH}_3$ (He et al., Chinese Phys. Lett. 2023), ${LaBeH}_8$ (Song et al., Phys. Rev. Lett. 2023), black phosphorous (Li et al., Proc. Natl. Acad. Sci. 2018; Jin et al., arXiv 2023), and violet (Wu et al., arXiv 2023) phosphorous to reveal the nonadiabaticity strength constant $\frac{T_{\theta }}{T_F}$ (where $T_{\theta }$ is the Debye temperature, and $T_F$ the Fermi temperature) in these superconductors. The analysis showed that the $\delta$-phase of titanium and black phosphorous exhibits $\frac{T_{\theta }}{T_F}$ scores that are nearly identical to those associated with A15 superconductors, while the studied hydrides and violet phosphorous exhibit constants in the same ballpark as those of $H_{3}S$ and ${LaH}_{10}$. Full article

Graphene is the first two-dimensional material that becomes the center material in various research areas of material science, chemistry, condensed matter, and engineering due to its advantageous properties, including larger specific area, lower density, outstanding electrical conductivity, and ease of processability. These properties attracted the attention of material researchers that resulted in a large number of publications on EMI shielding in a short time and play a central role in addressing the problems and challenges faced in this modern era of electronics by electromagnetic interference. After the popularity of graphene, the community of material researchers investigated other two-dimensional materials like MXenes, hexagonal boron nitride, black phosphorous, transition metal dichalcogenides, and layered double hydroxides, to additionally enhance the EMI shielding response of materials. The present article conscientiously reviews the current progress in EMI shielding materials in reference to two-dimensional materials and addresses the future challenges and research directions to achieve the goals. Full article

In this study, phosphorus-doped watermelon rind carbon material (WC-M) was prepared by a muffle furnace, and the adsorption performance of WC-M material to dyes was investigated. At the same time, the effects of dye concentration, pH, adsorption time, adsorption temperature, and other factors on the adsorption effect were investigated. In the experiment, a muffle furnace was used to carbonize the watermelon rind doped with phosphoric acid, which simplified the experimental operation. Regarding the results of SEM analysis, the surface structure of WC-M materials is diverse. Isothermal maps of nitrogen adsorption and desorption show that the material contains more microporous structures and exhibits more active sites. The experimental results show that WC-M materials show good adsorption properties against cationic dyes (malachite green, MG) and anionic dyes (active black, AB). The neutral condition is conducive to the adsorption of MG, and the alkaline condition is conducive to the adsorption of AB. The adsorption rate reaches a maximum in the initial stage of adsorption, the adsorption capacity reaches 50% of the total adsorption capacity within 10 minutes before the reaction, and then the adsorption capacity gradually decreases until the adsorption equilibrium. The adsorption mechanism was explored by the pseudo-first-order kinetic model, second-order kinetic model, and intraparticle diffusion model. At the same time, through the analysis of multiple isotherm models, the overall adsorption process followed the Langmuir isotherm model, the adsorption of MG was more inclined to monolayer electron adsorption, and the adsorption capacity reached 182.68 mg⋅g⁻¹. The reusability of WC-M materials in MG and AB adsorption was discussed. At this time, the concentrations of AB and MG were 120 mg⋅L⁻¹ and 150 mg⋅L⁻¹, and after 10 h of desorption, the desorption rates of MG and AB reached 67.7% and 83.3%, respectively; after five adsorption–desorption cycles, the adsorption rate of MG was still 78.5%, indicating that WC-M materials have good recovery effect. At the same time, the use of watermelon rind as an adsorption material belongs to the high-value application of watermelon rind, which belongs to “turning waste into treasure” and will not pose a certain threat to the environment. This experiment is also suitable for durian rind, pineapple rind, and other “waste” biomass materials, and the experiment has certain generalizations. Full article