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Using scanning electron microscopy (SEM), a small animal imaging system, and biological tissue sections, the relationships between the flapping vibrations in the hindwings of Trypoxylus dichotomus and their morphology, structure, and hemolymph dynamics were investigated. Based on these findings, a three-degree-of-freedom (3-DOF) model incorporating nano-mechanical properties was developed to investigate spanwise passive synergistic vibration reduction (PSVR) in the hindwing elements. To ensure precision, the Runge-Kutta and incremental harmonic balance (IHB) methods were employed for both solving and comparing solutions. Analysis of the spanwise force (FOX) signals confirmed the validity of the PSVR model. Parametric analysis revealed that reducing system mass and stiffness increased the resonance amplitude while shifting the resonance frequency in the opposite direction. The resonance frequency and flexible deformation amplitude of the hindwing system could be controlled by adjusting mass and stiffness within the synergistic framework. The mass and damping of the wing base, along with the stiffness of the wing membrane, were identified as critical factors in the system. This model provides valuable insights into the PSVR mechanism, potentially informing the design and manufacture of bionic flexible flapping wings.
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The protection of plants in mountainous and hilly areas differs from that in plain areas due to the complex terrain, which divides the work plot into many narrow plots. When designing the path planning method for plant protection UAVs, it is important to consider the generality in different working environments. To address issues such as poor path optimization, long operation time, and excessive iterations required by traditional swarm intelligence algorithms, this paper proposes a bionic three-dimensional path planning algorithm for plant protection UAVs. This algorithm aims to plan safe and optimal flight paths between work plots obstructed by multiple obstacle areas. Inspired by krill group behavior and based on group intelligence algorithm theory, the bionic three-dimensional path planning algorithm consists of three states: "foraging behavior", "avoiding enemy behavior", and "cruising behavior". The current position information of the UAV in the working environment is used to switch between these states, and the optimal path is found after several iterations, which realizes the adaptive global and local convergence of the track planning, and improves the convergence speed and accuracy of the algorithm. The optimal flight path is obtained by smoothing using a third-order B-spline curve. Three sets of comparative simulation experiments are designed to verify the performance of this proposed algorithm. The results show that the bionic swarm intelligence algorithm based on krill swarm behavior reduces the path length by 1.1~17.5%, the operation time by 27.56~75.15%, the path energy consumption by 13.91~27.35%, and the number of iterations by 46~75% compared with the existing algorithms. The proposed algorithm can shorten the distance of the planned path more effectively, improve the real-time performance, and reduce the energy consumption.
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Oral cancer represents a significant global public health challenge, contributing substantially to the incidence and mortality of cancer. Despite established risk factors such as tobacco use and alcohol consumption, early detection remains crucial for effective treatment. This study introduces a novel approach using a transistor-based biosensor system for detecting the P90 (CIP2A) protein. We tested the presence of CIP2A in human leukoplakia samples, which can undergo malignant conversion into aggressive oral squamous cell carcinoma. The method used commercially available glucose test strips functionalized with P90 antibodies, providing high sensitivity and a low limit of detection which was five orders lower than that of commercial ELISA kits. A specially designed printed circuit board (PCB) facilitated accurate measurements, and the device's performance was optimized through characteristic tests. Human sample testing validated the biosensor's effectiveness in distinguishing samples after cell lysis. This study contributes to advancing accurate and cost-effective diagnostic approaches for oral pre-cancer and cancer tissues.
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Técnicas Biosensibles , Leucoplasia Bucal , Saliva , Humanos , Leucoplasia Bucal/diagnóstico , Saliva/química , Biomarcadores de Tumor/análisis , Proteínas de la Membrana , Neoplasias de la Boca/diagnóstico , Ensayo de Inmunoadsorción EnzimáticaRESUMEN
Nanofiltration (NF) and reverse osmosis (RO) processes are physical separation technologies used to remove contaminants from liquid streams by employing dense polymer-based membranes with nanometric voids that confine fluids at the nanoscale. At this level, physical properties such as solvent and solute permeabilities are intricately linked to molecular interactions. Initially, numerous studies focused on developing macroscopic transport models to gain insights into separation properties at the nanometer scale. However, continuum-based models have limitations in nanoconfined situations that can be overcome by force field molecular simulations. Continuum-based models heavily rely on bulk properties, often neglecting critical factors like liquid structuring, pore geometry, and molecular/chemical specifics. Molecular/mesoscale simulations, while encompassing these details, often face limitations in time and spatial scales. Therefore, achieving a comprehensive understanding of transport requires a synergistic integration of both approaches through a multiscale approach that effectively combines and merges both scales. This review aims to provide a comprehensive overview of the state-of-the-art in multiscale modeling of transport through NF/RO membranes, spanning from the nanoscale to continuum media.
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The Pacific white shrimp Litopenaeus vannamei is a representative species of decapod crustacean and an economically important marine aquaculture species worldwide. However, research on the genes involved in muscle growth and development in shrimp is still lacking. MyoD is recognized as a crucial regulator of myogenesis and plays an essential role in muscle growth and differentiation in various animals. Nonetheless, little information is available concerning the function of this gene among crustaceans. In this study, we identified a sequence of the MyoD gene (LvMyoD) with a conserved bHLH domain in the L. vannamei genome. Phylogenetic analysis revealed that both the overall protein sequence and specific functional sites of LvMyoD are highly conserved with those of other crustacean species and that they are evolutionarily closely related to vertebrate MyoD and Myf5. LvMyoD expression is initially high during early muscle development in shrimp and gradually decreases after 40 days post-larval development. In adults, the muscle-specific expression of LvMyoD was confirmed through RT-qPCR analysis. Knockdown of LvMyoD inhibited the growth of the shrimp in body length and weight. Histological observation and transcriptome sequencing of muscle samples after RNA interference (RNAi) revealed nuclear agglutination and looseness in muscle fibers. Additionally, we observed significant effects on the expression of genes involved in heat shock proteins, myosins, actins, protein synthesis, and glucose metabolism. These findings suggest that LvMyoD plays a critical role in regulating muscle protein synthesis and muscle cell differentiation. Overall, this study highlights the involvement of LvMyoD in myogenesis and muscle growth, suggesting that it is a potentially important regulatory target for shrimp breeding efforts.
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Proteína MioD , Penaeidae , Filogenia , Animales , Penaeidae/genética , Penaeidae/crecimiento & desarrollo , Penaeidae/metabolismo , Proteína MioD/genética , Proteína MioD/metabolismo , Desarrollo de Músculos/genética , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Secuencia de AminoácidosRESUMEN
The prevalence of breast cancer in women underscores the urgent need for innovative and efficient detection methods. This study addresses this imperative by harnessing salivary biomarkers, offering a noninvasive and accessible means of identifying breast cancer. In this study, commercially available disposable based strips similar to the commonly used glucose detection strips were utilized and functionalized to detect breast cancer with biomarkers of HER2 and CA15-3. The results demonstrated limits of detection for these two biomarkers reached as low as 1 fg/ml much lower than those of conventional enzyme-linked immunosorbent assay in the range of 1â¼4 ng/ml. By employing a synchronized double-pulse method to apply 10 of 1.2 ms voltage pulses to the electrode of sensing strip and drain electrode of the transistor for amplifying the detected signal, and the detected signal was the average of 10 digital output readings corresponding to those 10 voltage pulses. The sensor sensitivities were achieved approximately 70/dec and 30/dec for HER2 and CA15-3, respectively. Moreover, the efficiency of this novel technique is underscored by its swift testing time of less than 15 ms and its minimal sample requirement of only 3 µl of saliva. The simplicity of operation and the potential for widespread public use in the future position this approach as a transformative tool in the early detection of breast cancer. This research not only provides a crucial advancement in diagnostic methodologies but also holds the promise of revolutionizing public health practices.
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Precise optical mode matching is of critical importance in experiments using squeezed-vacuum states. Automatic spatial-mode matching schemes have the potential to reduce losses and improve loss stability. However, in quantum-enhanced coupled-cavity experiments, such as gravitational-wave detectors, one must also ensure that the sub-cavities are also mode matched. We propose what we believe to be a new mode sensing scheme, which works for simple and coupled cavities. The scheme requires no moving parts, nor tuning of Gouy phases. Instead a diagnostic field tuned to the HG20/LG10 mode frequency is used. The error signals are derived to be proportional to the difference in waist position, and difference in Rayleigh ranges, between the sub-cavity eigenmodes. The two error signals are separable by 90 degrees of demodulation phase. We demonstrate reasonable error signals for a simplified Einstein Telescope optical design. This work will facilitate routine use of extremely high levels of squeezing in current and future gravitational-wave detectors.
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Waste three-way catalysts (TWCs) have attracted much attention due to the presence of platinum group metals (PGMs) and hazardous substances such as heavy metals and organic matter. The extraction of PGMs from waste TWCs using hydrochloric acid (HCl) has been extensively researched. However, the addition of oxidizing agents like H2O2 and aqua regia is necessary to facilitate PGMs dissolution, which poses significant environmental and operational hazards. Hence, developing a green PGMs recovery process without oxidants is imperative. Previously, we investigated the process of Li2CO3 calcination pretreatment to enhance the leaching of PGMs from waste TWCs by HCl, focusing on the process and mechanism of Li2CO3 calcination pretreatment. In this study, we focused on the leaching process of HCl after pretreatment. Our investigation includes a detailed examination of leaching kinetics and mechanisms. The optimal leaching conditions were: leaching temperature of 150 °C, leaching time of 2 h, HCl concentration of 12 M, and liquid-solid ratio of 10 mL/g. The experiments resulted in maximum leaching rates of about 96%, 97%, and 97% for Pt, Pd, and Rh, respectively. However, given the presence of heavy metals, attention needs to be paid to the harmless treatment of waste acids and leaching residues. The Pt and Pd leaching process is controlled by a mixture of interfacial chemical reactions and internal diffusion, and dominated by internal diffusion, while the leaching process of Rh is controlled by interfacial chemical reactions. Li+ in Li2PtO3, Li2PdO2, and Li2RhO3 preferentially leached and underwent ion-exchange reactions with H+, promoting the dissolution of Pt, Pd, and Rh in HCl.
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Metales Pesados , Platino (Metal) , Ácido Clorhídrico/química , Peróxido de Hidrógeno/química , Metales Pesados/química , Litio , Oxidantes , ReciclajeRESUMEN
The targeted capture of platinum from complex and harsh acidic digests such as those platinum-containing secondary resources is essential from the perspectives of green development. Here, a polyamine chelating resin (CMPs-PEI) with excellent selectivity and acid resistance was prepared by a nucleophilic substitution reaction using chloromethylated polystyrene as the parent and polyethyleneimine as the modifier. The experimental results revealed that the adsorbent showed excellent adsorption effect on platinum under different acidities, and its maximum adsorption capacity was up to 337 mg/g at pH 2. More impressively, a rather high capacity of 162.41 mg/g was achieved in 1 + 1 aqua regia (pH -0.7), which was much higher than other adsorbent materials under the same conditions. In addition, the recovery of platinum by CMPs-PEI in practical platinum-containing iron concentrate abatement solution was 100 %. Mechanistic studies showed that the protonated amine groups on CMPs-PEI bound PtCl62- and partially reduced PtCl42- by electrostatic attraction. Meanwhile, the excellent regeneration performance of CMPs-PEI indicated that it showed great potential for green and economic recovery of precious metal ions.
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Ácido Clorhídrico , Platino (Metal) , Adsorción , CinéticaRESUMEN
Recovery of platinum group metals (PGMs) from waste three-way catalysts (TWCs) was usually achieved by dissolving them in an acid solution. However, their dissolution requires the addition of oxidizing agents such as Cl2 and aqua regia, which could cause high environmental risks. Therefore, the development of new methods without the addition of oxidant agents will contribute to the green recovery of PGMs. In this paper, the process and mechanism of PGMs recovery from waste TWCs by Li2CO3 calcination pretreatment-HCl leaching were studied in detail, and molecular dynamics calculations were performed for the formation processes of Pt, Pd, and Rh complex oxides. The results showed that the leaching rates of Pt, Pd, and Rh could reach about 95%, 98%, and 97%, respectively, under the optimal conditions. Li2CO3 calcination pretreatment cannot only oxidize Pt, Pd, and Rh metals to HCl-soluble Li2PtO3, Li2PdO2, and Li2RhO3, but also remove the carbon accumulation in waste TWCs and open the wrapping of PGMs by the substrate and Al2O3 coating. The embedding of Li and O atoms in metallic Pt, Pd, and Rh is an interacting embedding process. Although the Li atoms are faster than O, O will accumulate on the metal surface first before embedding.
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BACKGROUND: To investigate the synergic effect and underlying mechanism of Endostar, a recombinant human endostatin used for anti-angiogenesis, in radiotherapy for cervical cancer. METHODS: The Cell Counting Kit-8 (CCK-8) assay and plate cloning experiment were first employed to analyze the proliferation of HeLa and SiHa cervical cancer cells and human umbilical vein vascular endothelial cells (HUVECs). Flow cytometry was used to detect apoptosis and cell cycle progression. A tube formation assay was used to assess angiogenesis in vitro. The expression of gamma H2A histone family member X (γ-H2AX) and activation of the vascular endothelial growth factor receptor (VEGFR) signaling pathway were detected by immunofluorescence and western blotting, respectively. In a HeLa xenograft model, tumor tissue expression of CD31 and alpha smooth muscle actin and serum expression of VEGF-A were detected by immunohistochemistry (IHC) and enzyme-linked immunosorbent assay, respectively. RESULTS: The CCK-8 and plate cloning assays showed that Endostar and radiotherapy synergistically inhibited the growth of HUVECs but not HeLa and SiHa cells. The flow cytometric results showed that Endostar only promoted radiotherapy-induced apoptosis and G2/M phase arrest in HUVECs (p < 0.05). Endostar combined with radiotherapy also significantly inhibited tube formation by HUVECs (p < 0.05). Furthermore, Endostar inhibited the radiotherapy-induced expression of γH2AX (p < 0.05) and phosphorylation of VEGFR2/PI3K/AKT/DNA-PK in HUVECs (p < 0.05). IHC showed that Endostar enhanced the inhibitory effect of radiotherapy on the microvessel density in xenograft tumor tissues (p < 0.05), as well as serum VEGF-A expression (p < 0.05). The tumor volume in the combination therapy groups (1200 mm3) was significantly lower than in the control group (2500 mm3; p < 0.05). CONCLUSIONS: Our findings provide experimental evidence and a theoretical basis for the application of Endostar in combination with irradiation for anti-cervical cancer treatment.
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Endostatinas , Neoplasias del Cuello Uterino , Inhibidores de la Angiogénesis/farmacología , Animales , Proliferación Celular , Modelos Animales de Enfermedad , Endostatinas/farmacología , Femenino , Xenoinjertos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Ratones , Neovascularización Patológica/radioterapia , Fosfatidilinositol 3-Quinasas , Proteínas Recombinantes , Neoplasias del Cuello Uterino/radioterapia , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Dielectric behavior of electrolyte aqueous solutions with various concentrations in a cylindrical nanopore of MCM 41 silica has been investigated. The effect of confinement is investigated by using isothermal-isosurface-isobaric statistical ensemble, which has proved to be an effective alternative to the Grand Canonical Monte Carlo (GCMC) simulation method. Several single-salt solutions have been considered (e.g., NaCl, NaI, BaCl2, MgCl2) in order to investigate the effect of ion polarizability, ion size, and ion charge. The effect of salt concentration has also been addressed by considering NaCl solutions at different concentrations (i.e., 0.1 mol/L, 0.5 mol/L, and 1 mol/L). The motivation in performing this integrated set of simulations is to provide deep insight into the dielectric exclusion in NF theory that plays a significant role in separation processes. It was shown that the dielectric constant increased when ions were added to water inside the nanopore (with respect to the dielectric constant of confined pure water) unlike what was obtained in the bulk phase and this phenomenon was even more pronounced for electrolytes with divalent ions (MgCl2 and BaCl2). Therefore, our simulations indicate opposite effects of ions on the dielectric constant of free (bulk) and nanoconfined aqueous solutions.
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Platinum group metals (PGMs), especially platinum (Pt), palladium (Pd), and rhodium (Rh), are widely used in automotive three-way catalysts (TWCs). PGM resources are scarce and unevenly distributed, with global reserves of 69,000 t in 2020, of which more than 99% are concentrated in South Africa, Russia, Zambia, and the United States. However, the demand for PGMs worldwide is growing continually, especially in China. The recovery of PGMs from spent TWCs not only can alleviate the contradiction between supply and demand but also have good economic and environmental benefits. This paper briefly analyzes the market demand for Pt, Pd, and Rh in the global automotive industry in recent years, emphasizing the importance of waste TWC recycling. It also presents the current status of waste TWC management in some countries, especially China, and critically reviews the main recycling strategies for waste TWCs. On this basis, suggestions for strengthening the management of waste TWCs in China are put forward, and the future development trend of recycling technology is foreseen. The purpose of this paper is to provide some valuable references for the decision-makers of waste TWC management, and hopefully to provide inspiration for related scholars on the future research direction of waste TWC recycling technology.
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Rodio , Administración de Residuos , Catálisis , Paladio , Platino (Metal) , ReciclajeRESUMEN
OBJECTIVE: To investigate the short-term efficacy and safety of Endostar combined with concurrent chemoradiotherapy in the treatment of locally advanced cervical squamous cell carcinoma (LACSC). METHODS: A total of 91 patients with LACSC admitted to the First Affiliated Hospital of Anhui Medical University from June 2019 to December 2020 were randomly assigned to either the experimental group (n = 48) or control group (n = 43). The control group received radiotherapy for cervical cancer and paclitaxel combined with platinum chemotherapy (CCRT), and the experimental group received Endostar continuous intravenous infusion of anti-angiogenic therapy plus CCRT. The short-term efficacy, common clinical indicators, tumor indicators, changes in serum vascular endothelial growth factor-A (VEGF-A), and the occurrence of adverse events (AEs) were explored after treatment. RESULTS: Compared with the control group, the complete response (CR) rate in the experimental group was significantly increased (83.33% vs 65.12%, P < 0.05). Both routine indicators and tumor indicators in the two groups were significantly decreased compared to before treatment. Compared with the control group, patients in the experimental group had higher incidences of neutropenia, hypertension, and infection, but lower incidence of nausea. After treatment, the serological expression of VEGF-A was significantly decreased in both groups. CONCLUSION: Endostar combined with CCRT in the treatment of LACSC can further improve the efficacy of CR rate and significantly reduce serum tumor indicators and VEGF-A levels, with mild and controllable AEs. Endostar combined with CCRT is expected to be a new treatment regimen for LACSC.
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Dielectric behavior of salt aqueous solutions with various concentration in pristine and oxide graphene nanochannels has been investigated by means of molecular dynamic simulations. The motivation in performing this integrated set of simulations was to provide deep insight into the interaction between the size of the enclosure and the oxidation degree of the membrane sheets on the dielectric properties. It was shown that the dielectric permittivity of both aqueous and NaCl solution in confined phase exhibits an anisotropic behavior. The in-plane component decreases with the increase of the concentration of NaCl solution while an increase of the out-of-plane dielectric is observed and these out-of-plane components exhibit a non-monotonous trend and thus exist a critical concentration of NaCl solution with 0.2 mol/L and 0.4 mol/L for both pristine and oxide graphene nanochannels, respectively. This peculiar dielectric behavior results from the addition of ions that significantly perturb the hydrogen bonding network of the confined system, and hence leading to a fluctuation of dipolar of water molecules and dielectric permittivity.
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Lithium-ion batteries (LIBs) were used extensively in people's lives, especially with the vigorous promotion of new energy vehicles, which led to the generation of a large number of waste LIBs. In consideration of the enormous quantity, environmental risk, and resource properties, many countries have issued a series of laws and regulations to manage waste LIBs and developed a lot of recycling technologies. As the biggest producer of batteries in the world, China has also taken necessary measures to deal with this situation. This paper presents the latest regulations of waste LIBs in China and reviews the recycling strategies of waste LIBs, especially physical recycling methods. Based on the analysis of the current management status of waste LIBs in China and the recycling technologies, some management suggestions, and a complete closed-circuit recycling process including cascade utilization and resource recovery were put forward. A rough economic evaluation of the process was also conducted to demonstrate the economic feasibility of the proposed process. The purpose of this paper is to provide some valuable references for decision-making bodies in the improvement of waste lithium-ion battery management and to provide an environmentally friendly and industrial feasible recycling process for reference.
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In this study, a complete steric, electrostatic, and dielectric mass transfer model is applied to investigate the separation mechanism of typical antibiotic sulfadiazine by NF90, NF270, VNF-8040 and TMN20H-400 nanofiltration membranes. FTIR and XPS analysis clearly indicate that the membranes we used possess skin layers containing both amine and carboxylic acid groups that can be distributed in an inhomogeneous fashion, leading to a bipolar fixed charge distribution. We compare the theoretical and experimental rejection rate of the sulfadiazine as a function of the pressure difference across the nanopore for the four polyamide membranes of inhomogeneously charged nanopores. It is shown that the rejection rate of sulfadiazine obtained by the solute transport model has similar qualitative results with that of experiments and follows the sequence: RNF90>RVNF2-8040>RNF270>RTMN20H-400. The physical explanation can be attributed to the influence of the inhomogeneous charge distribution on the electric field that arises spontaneously so as to maintain the electroneutrality within the nanopore.
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In our original work, the computation of the density of liquid in a silica hydrophilic nanopore was executed by the grand canonical Monte Carlo (GCMC) simulation to investigate the spatial dielectric properties of water in a confined phase. We found that the average values of the dielectric constants were very close and almost independent of the number of concentric radial shells. In response to the comment by S. Mondal and B. Bagchi, we clarify the issues of reproducibility of bulk value of the dielectric constant of water and dielectric anisotropy.
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Liquid crystal (LC), as a crucial component of liquid crystal display (LCD), improperly treatment of which will possibly impair ecosystems and human health. In view of the advantages of hydrothermal reaction and microwave irradiation, this paper intensively studied the process of microwave-assisted hydrothermal (MWAH) decomposition of LC wastes. The experimental materials include a kind of refractory fluorinated liquid crystal commonly used in thin-film transistor LCD, and its mixture with the other two typical liquid crystal monomers in the waste low-end display panels. Under the MWAH process, the optimized condition for thorough decomposition of 0.67 g.L-1 fluorinated liquid crystal is 0.653 mol.L-1 H2O2, 1 g.L-1 AC, 300 mL water, 250 °C and 7 min. The superiority of microwave in enhancing hydrothermal treatment efficiency was verified by the first-order kinetic reaction equation fitted for the decomposition process under optimal condition, along with two possible decomposition pathways tentatively proposed after characterizing the intermediate products. Under the same condition, 1 g.L-1 mixture of fluorinated liquid crystal and the other two liquid crystal monomers were entirely decomposed with no harmful byproduct detected, suggesting that microwave irradiation could effectively promote the hydrothermal decomposition of liquid crystal wastes.
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Indium is one of the components with great recycling value in waste LCDs. Degradation of organic materials and the remain of indium in the solid phase can be simultaneously achieved by hydrothermal pretreatment via parameter regulation. Indium was transferred from the solid phase to the liquid phase by using sulfuric acid after hydrothermal pretreatment. Di-(2-ethylhexyl) phosphoric acid diluted by sulfonated kerosene and hydrochloric acid were used as extractant and stripping agent respectively to purify and concentrate indium from acidic leaching solution. The results indicated that the leaching yield of indium reached 100% under the optimal condition of reaction time of 40 min, reaction temperature of 70-80 °C, acid concentration of 0.5 M and solid-liquid (S/L) ratio of 1:2 g/mL. Given conditions of extraction time of 3 min at the organic phase to aqueous phase (O/A) ratio of 1:10 by 20% D2EHPA and stripping time of 10 min at the (O/A) ratio of 10:1 by 4 M HCl, the recovery efficiency of indium reached 97.25%. In addition, acid leaching process did not change the surface topography and molecular structure of glass substrate and had no negative effect on subsequent recycling of glass. The kinetic equation of leaching yield and reaction time at the temperature of 80 °C is 1 - (1 - y)1/3 = 0.0215 t. The reaction activation energy of metal indium leaching process is 50.64 kJ/mol.