Recent Progress and Future Prospects on All-Organic Polymer Dielectrics for Energy Storage Capacitors.

With the development of advanced electronic devices and electric power systems, polymer-based dielectric film capacitors with high energy storage capability have become particularly important. Compared with polymer nanocomposites with widespread attention, all-organic polymers are fundamental and have been proven to be more effective choices in the process of scalable, continuous, and large-scale industrial production, leading to many dielectric and energy storage applications. In the past decade, efforts have intensified in this field with great progress in newly discovered dielectric polymers, fundamental production technologies, and extension toward emerging computational strategies. This review summarizes the recent progress in the field of energy storage based on conventional as well as heat-resistant all-organic polymer materials with the focus on strategies to enhance the dielectric properties and energy storage performances. The key parameters of all-organic polymers, such as dielectric constant, dielectric loss, breakdown strength, energy density, and charge-discharge efficiency, have been thoroughly studied. In addition, the applications of computer-aided calculation including density functional theory, machine learning, and materials genome in rational design and performance prediction of polymer dielectrics are reviewed in detail. Based on a comprehensive understanding of recent developments, guidelines and prospects for the future development of all-organic polymer materials with dielectric and energy storage applications are proposed.

An Anti-Scaling Strategy for Electrochemical Wastewater Treatment: Leveraging Tip-Enhanced Electric Fields.

Electrode scaling poses a critical barrier to the adoption of electrochemical processes in wastewater treatment, primarily due to electrode inactivation and increased internal reactor resistance. We introduce an antiscaling strategy using tip-enhanced electric fields to redirect scale-forming compounds (e.g., Mg(OH)2 and CaCO3) from the electrode-electrolyte interface to the bulk solution. Our study utilized Cu nanowires (Cu NW) with high-curvature nanostructures as the cathode, in contrast to Cu nanoparticles (Cu NP), Cu foil (CF), and Cu mesh (CM), to evaluate the electrochemical nitrate reduction reaction (NO3RR) performance in hard water conditions. The Cu NW/CF cathode demonstrated superior NO3RR efficiency, with an apparent rate constant (Kapp) of 1.04 h-1, significantly outperforming control electrodes under identical conditions (Kapp < 0.051 h-1). Through experimental and theoretical analysis, including COMSOL simulations, we show that the high-curvature design of Cu NW induced localized electric field enhancements, propelling OH- ions away from the electrode surface into the bulk solution, thus mitigating scale formation on the cathode. Testing with real nitrate-contaminated wastewater confirms that the Cu NW/CF cathode maintained excellent denitrification efficiency over a 60-day period. This study offers a promising perspective on preventing electrode scaling in electrochemical wastewater treatment, paving the way for more efficient and sustainable practices.

Speciation and Possible Origins of Organosulfur Compounds in Rice Paddy Soils Affected by Acid Mine Drainage.

Although sulfur cycling in acid mine drainage (AMD)-contaminated rice paddy soils is critical to understanding and mitigating the environmental consequences of AMD, potential sources and transformations of organosulfur compounds in such soils are poorly understood. We used sulfur K-edge X-ray absorption near edge structure (XANES) spectroscopy to quantify organosulfur compounds in paddy soils from five AMD-contaminated sites and one AMD-uncontaminated reference site near the Dabaoshan sulfide mining area in South China. We also determined the sulfur stable isotope compositions of water-soluble sulfate (δ34SWS), adsorbed sulfate (δ34SAS), fulvic acid sulfur (δ34SFAS), and humic acid sulfur (δ34SHAS) in these samples. Organosulfate was the dominant functional group in humic acid sulfur (HAS) in both AMD-contaminated (46%) and AMD-uncontaminated paddy soils (42%). Thiol/organic monosulfide contributed a significantly lower proportion of HAS in AMD-contaminated paddy soils (8%) compared to that in AMD-uncontaminated paddy soils (21%). Within contaminated soils, the concentration of thiol/organic monosulfide was positively correlated with cation exchange capacity (CEC), moisture content (MC), and total Fe (TFe). δ34SFAS ranged from -6.3 to 2.7‰, similar to δ34SWS (-6.9 to 8.9‰), indicating that fulvic acid sulfur (FAS) was mainly derived from biogenic S-bearing organic compounds produced by assimilatory sulfate reduction. δ34SHAS (-11.0 to -1.6‰) were more negative compared to δ34SWS, indicating that dissimilatory sulfate reduction and abiotic sulfurization of organic matter were the main processes in the formation of HAS.

Polymer Dielectrics with Outstanding Dielectric Characteristics via Passivation with Oxygen Atoms through C-F Vacancy Carbonylation.

The development of advanced electrical equipment necessitates polymer dielectrics with a higher electric strength. Unfortunately, this bottleneck problem has yet to be solved because current material modification methods do not allow direct control of deep traps. Here, we propose a method for directly passivating deep traps. Measurements of nanoscale microregion charge characteristics and trap parameters reveal a significant reduction in the number of deep traps. The resulting polymer dielectric has an impressively high electrical strength, less surface charge accumulation, and a significantly increased flashover voltage and breakdown strength. In addition, the energy storage density is increased without sacrificing the charge-discharge efficiency. This reveals a new approach to increasing the energy storage density by reducing the trap energy levels at the electrode-dielectric interface. We further calculated and analyzed the microscopic physical mechanism of deep trap passivation based on density functional theory and characterized the contributions of orbital composition and orbital hybridization.

Influence of dissolved organic matter with different molecular weight from chicken manure on ferrihydrite adsorption and re-release of antimony(V).

Applying organic fertilizer is the main way to enhance soil fertility through the interfacial reaction between mineral and dissolved organic matter (DOM). However, the interfacial reaction between minerals and DOM may influence antimony(V) (Sb(V)) mobility in agricultural soils around antimony mines. In our study the ferrihydrite (Fh) was chosen as a representative mineral, to reveal the effect of its interaction with chicken manure organic fertilizer (CM-DOM) with Fh on Sb(V) migration. In this study, we investigated different organic matter molecular weights and C/Fe molar ratios. Our findings indicated that the addition of CM-DOM decreased the adsorption of Sb(V) by Fh and promoted the re-release of Sb(V) adsorbed on Fh. This effect was enhanced by increasing the C/Fe molar ratio. Fh mainly affects its interaction with Sb(V) through electrostatic gravitational interaction and ligand exchange, but the presence of CM-DOM weakens the electrostatic interaction between Fh and Sb(V) as well as competes with Sb(V) for the hydroxyl reactive site on Fh surface. In addition, the smaller molecular weight fraction (<10 kDa) of CM-DOM has higher aromaticity and hydrophobicity, which potentially leads to more intense competition with Sb(V) for the reaction sites on Fh. Therefore, the application of organic fertilizer may promote Sb(V) migration, posing significant risks to soil ecosystems and human health, which should be a concern in field soil cultivation.

Facet-Dependent Competitive Adsorption Mechanisms of Chromate and Oxalic Acid on γ-FeO(OH) Nanocrystals.

Facet-dependent toxic metal adsorption of iron oxides widely occurred in natural environments. It is known that organic acids can alter the adsorption behaviors of trace elements by cooperative or competitive effects. However, the coadsorption mechanisms of the specific facets are still not fully understood. In the current investigation, Cr(VI) adsorption onto the lepidocrocite (γ-FeO(OH))-exposed facets in the presence of oxalic acid (OA) was studied using macroexperiments, in situ attenuated total reflectance Fourier transform infrared spectroscopy, X-ray adsorption fine structure, and density functional theory calculations. Rod-like lepidocrocite (R-LEP) with a high ratio of {001}/{010} facet showed excellent Cr(VI) adsorption capacity than that of plate-like lepidocrocite (P-LEP, the dominant facet is {010}) in the absence/presence of OA. Interestingly, OA reacted with R-LEP would be easier to diminish Cr(VI) adsorption than with P-LEP. The competitive adsorption occurred on the {001} facet due to the formation of inner-sphere OA configurations (monodentate mononuclear and bidentate mononuclear structures) and a bidentate binuclear Cr(VI) complex. However, OA coordinated with {010} facets via the outer-sphere complexes, while Cr(VI) could form a protonated monodentate binuclear configuration. These observations suggest that the competitive adsorption processes between OA and Cr(VI) exhibit facet dependence. Furthermore, lepidocrocite-exposed facets determine the interfacial interactions and geochemical behaviors of Cr(VI) in polluted environments.

Effects and mechanisms of anion and cation on the gelation of nanosilica sol by all-atom molecular dynamics simulation: promotion or inhibition?

Nanosilica sol (NSS) is prone to gelation due to the condensation of silicon hydroxyl at normal temperature and pressure, which is further exacerbated by the addition of electrolytes during production. Therefore, the effects of ions and the mechanism of gelation of NSS are crucial for its stability. Herein, all-atom molecular dynamics (AAMD) was carried out to explore the effects and mechanisms of cations (K+, Na+, Ca2+) and anions (Cl-, NO3-, SO42-, PO43-) on the sol-gel transition. Results indicated that highly electrophilic cations (e.g., Ca2+) and anions with slightly stronger nucleophilicity than Si(OH)3O- (e.g., NO3-) could inhibit gelation by preventing Si(OH)4 and Si(OH)3O- from approaching the silica surface. Such inhibition is more pronounced in NSS with larger particle sizes. Our findings offer some critical insights into the effects of ions on the gel stability of NSS, which also contributes significantly to screening suitable electrolytes for the production of NSS.

High-Temperature Polymer Dielectrics Designed Using an Invertible Molecular Graph Generative Model.

Generating new molecules with the desired physical or chemical properties is the key challenge of computational material design. Deep learning techniques are being actively applied in the field of data-driven material informatics and provide a promising way to accelerate the discovery of innovative materials. In this work, we utilize an invertible graph generative model to generate hypothetical promising high-temperature polymer dielectrics. A molecular graph generative model based on the invertible normalizing flow is trained on a data set containing 250k polymer molecular graphs (mostly generated by an RNN-based generative model) to learn the invertible transformations between latent distributions and molecular graph structures. When generating molecular graphs, a sample vector is drawn from the latent space, and then an adjacency tensor and node attribute matrix are generated through two invertible flows in two steps and assembled into a molecular graph. The model has the merits of exact likelihood training and an efficient one-shot generation process. The learned latent space is used to generate polymers with a high glass-transition temperature (Tg) and a wide band gap (Eg) for the application of high-temperature energy storage film capacitors. This work contributes to the efficient design of high-temperature polymer dielectrics by using deep generative models.

Hydrogen-Donor-Controlled Polybrominated Dibenzofuran (PBDF) Formation from Polybrominated Diphenyl Ether (PBDE) Photolysis in Solutions: Competition Mechanisms of Radical-Based Cyclization and Hydrogen Abstraction Reactions.

Polybrominated dibenzofurans (PBDFs) are characteristic dioxin-like products of polybrominated diphenyl ether (PBDE) photolysis. In this study, competition mechanisms of radical-based cyclization and hydrogen abstraction reactions are proposed in PBDF formation. Commonly, the ortho C-Br bond dissociation during photolysis generates aryl radicals, which undergo intramolecular cyclization to form PBDFs or hydrogen abstraction with hydrogen donors (such as organic solvents and water) to form lower brominated PBDEs. By using 2,4,4'-tribromodiphenyl ether (BDE-28) as the model reactant, the experimental PBDF formation ratios in various solutions are explained quantitatively by the calculated rate constants of cyclization and hydrogen abstraction reactions using the density functional theory (DFT) method. The solvent effect of pure and mixed solvents on PBDF formation is illustrated successfully. The structure-related hydrogen donation ability for hydrogen abstraction controls the bias of competition reactions and influences PBDF formation. Water resulted to be the most significant generation of PBDFs. Fulvic and humic acid display higher hydrogen donation ability than small-molecule organics due to the partitioning effect in aqueous solution. Quantitative structure-activity relationship (QSAR) models of the calculated rate constants for 512 cyclization and 319 hydrogen abstraction reactions using 189 PBDEs as the initial reactants in water are established, revealing the high risk of PBDF formation in aqueous solution.

Alternating [1.1.1]Propellane-(Meth)Acrylate Copolymers: A New Class of Dielectrics with High Energy Density for Film Capacitors.

Polymer dielectrics with high energy density are of urgent demand in electric and electronic devices, but the tradeoff between dielectric constant and breakdown strength is still unsolved. Herein, the synthesis and molar mass control of three alternating [1.1.1]propellane-(meth)acrylate copolymers, denoted as P-MA, P-MMA, and P-EA, respectively, are reported. These copolymers exhibit high thermal stability and are semi-crystalline with varied glass transition temperatures and melting temperatures. The rigid bicyclo[1.1.1]pentane units in the polymer backbone promote the orientational polarization of the polar ester groups, thus enhancing the dielectric constants of these polymers, which are 4.50 for P-EA, 4.55 for P-MA, and 5.11 for P-MMA at 10 Hz and room temperature, respectively. Moreover, the high breakdown strength is ensured by the non-conjugated nature of bicyclo[1.1.1]pentane unit. As a result, these copolymers show extraordinary energy storage performance; P-MA exhibits a discharge energy density of 9.73 J cm-3 at 750 MV m-1 and ambient temperature. This work provides a new type of promising candidates as polymer dielectrics for film capacitors, and offers an efficient strategy to improve the dielectric and energy storage properties by introducing rigid non-conjugated bicyclo[1.1.1]pentane unit into the polymer backbone.

Adsorption behavior of hierarchical porous biochar from shrimp shell for tris(2-chloroethyl) phosphate (TCEP): Sorption experiments and DFT calculations.

Tris(2-chloroethyl) phosphate (TCEP) as a new type of flame retardant exists in various water environments, causing great risks to humans and the environment. In this study, shrimp shell was used to prepare an economical and environmental-friendly adsorbent for the efficient removal of TCEP. The systematic studies including characterization, removal performance, and adsorption mechanism of shrimp shell biochar toward TCEP were carried out. Adsorption kinetics and thermodynamics showed that fast equilibrium reached within 30 min, the maximum adsorption capacity qm was 108 µmol g-1 at 298 K, and the adsorption process is spontaneous and exothermic. The environmental factor, such as temperature, pH, inorganic anions and organic matter hardly affected the adsorption performance. Structural characterization indicated that the hierarchical porous structure of shrimp shell biochar is the key to excellent adsorption performance. The adsorption mechanisms were further revealed using density functional theory (DFT) calculations, and the hydrogen bond, van der Waals interactions, Cl-H interactions, and pi-H interactions were identified as potential interaction mechanisms between TCEP and specific biochar structures. The calculated binding energy between TCEP and simplified biochar structure suggested that oxygen-containing groups especially carboxyl, hydroxyl and aldehyde facilitate the adsorption. Our work not only provides a novel strategy for the quick remediation of organophosphate-contaminated water environments but also offers new opportunities for crustacean waste biomass valorization.

Oxidation of 1,3-diphenylguanidine (DPG) by goethite activated persulfate: Mechanisms, products identification and reaction sites prediction.

As emerging pollutants continue to be discovered, studies on the degradation behavior of emerging pollutants have proliferated, but few studies have focused on the reactivity of the new pollutants themselves. The work investigated the oxidation of a representative roadway runoff-derived organic contaminant, 1,3-diphenylguanidine (DPG) by goethite activated persulfate (PS). DPG exhibited the highest degradation rate (kd = 0.42 h-1) with present of PS and goethite at pH 5.0, then started to decrease with increasing pH. Chloride ion inhibited DPG degradation by scavenging HO·. Both HO· and SO4-· were generated in goethite activated PS system. Competitive kinetic experiments and flash photolysis experiments were conducted to investigate free radical reaction rate. The second-order reaction rate constants for DPG reacting with HO· and SO4-· were quantified (kDPG + HO·,kDPG + SO4-·), which both reached above 109 M-1 s-1. Chemical structures of five products were identified, four of them were previously detected in DPG photodegradation, bromination and chlorination processes. By density functional theory (DFT) calculations, ortho- and para- C were more easily attacked by both HO· and SO4-·. Abstraction of H on N by HO· and SO4-· were the favorable pathways, and the product TP-210 might be generated by cyclization of DPG radical from abstraction of H on N (3). The results of this study help us to better understand the reactivity of DPG with SO4-· and HO·.

Kinetics, mechanism, and application of sodium persulfate activated by sodium hydroxide for removing 1,2-dichloroethane from groundwater.

1,2-Dichloroethane (1,2-DCA) is a common compound found in groundwater contaminated with organics. This compound is difficult to remove from groundwater and has the potential to inflict significant harm on human health and the environment. This study used sodium persulfate (Na2S2O8) activated by sodium hydroxide (NaOH) to remove 1,2-DCA from aqueous solutions. Density functional theory was employed to calculate the potential energy surface of the reactants, intermediates, transient states, and products to thoroughly analyze the degradation pathways. The computations were performed in combination with in situ remediation of a 1,2-DCA plume from a point source to verify the industrial applicability of the technology. The results showed the 1,2-DCA removal efficiency was impacted considerably by the Na2S2O8 dosage and the dosing sequence of Na2S2O8 and NaOH, with the mean removal ratio reaching 96.24%. A free radical reaction was the main pathway of 1,2-DCA degradation; superoxide radical (O2•-) existed stably and played a key role in the reaction, and the main transformation proceeded via a vinyl chloride intermediate. The maximum removal of 1,2-DCA reached 91.79% in the in situ remediation. The developed technology exhibits important advantages in enabling flexible control over chemical dosages, long durations of effective activity, and rapid full-cycle remediation.

Transport and fate of Cu and Cd in contaminated paddy soil under acid mine drainage.

Long-term heavy metals accumulation caused by acid mine drainage (AMD) irrigation in paddy soils poses a severe threat to environmental health. However, the soil adsorption mechanisms under AMD flooding remain unclear. This study provides key insights into the fate of heavy metals in soil, particularly the retention and mobility mechanisms of Cu (copper) and Cd (cadmium) after AMD flooding. The migration and fate of Cu and Cd in uncontaminated paddy soils treated by AMD in Dabaoshan Mining area was investigated via column leaching experiments in the laboratory. The maximum adsorption capacities of Cu (658.04 mg kg-1) and Cd (335.20 mg kg-1) cations were predicted and the breakthrough curves were fitted using the Thomas and Yoon-Nelson models. Our findings demonstrated that Cd was more mobile than Cu. Furthermore, the soil had a greater adsorption capacity for Cu than Cd. Tessier's five-step extraction method was used to determine Cu and Cd fractions in leached soils at different depths and times. After AMD leaching, the relative and absolute concentrations of the easily mobile forms were all increased at different soil depths, thus increasing the potential risk to the groundwater system. Mineralogical characterization of the soil indicated that AMD flooding leads to the formation of mackinawite. This study provides insights into the distribution and transportation processes of soil Cu and Cd and their ecological effects under AMD flooding, as well as a theoretical basis for the establishment of corresponding geochemical evolution models and environmental governance in mining areas.

Fe(II)-mediated transformation of schwertmannite associated with calcium from acid mine drainage treatment.

Schwertmannite is an important Fe(III)-oxyhydroxysulfate in acid mine drainage (AMD) polluted areas and its stability depends on surrounding environmental factors and previously bound elements. The treatment and neutralization of AMD normally involve the use of lime, which leads to the discharge of abundant Ca in the mining area. Such an environmental disturbance brings up an important and less considered problem of how the reductive transformation of schwertmannite associated with coexisting Ca occurred. Here, the Fe(II)-mediated transformation of Ca-adsorbed schwertmannite and subsequent Ca repartitioning behaviors were investigated. Results showed that adsorbed Ca had a weak inhibitory effect on Fe(II)-mediated schwertmannite transformation. Release of SO42- and SEM images both indicated that transformation rates of schwertmannite decreased under the influence of adsorbed Ca. XRD patterns indicated that adsorbed Ca altered schwertmannite transformation pathways and product compositions upon treatment with 0.4 mmol/L Fe(II). The end products of Sch notably contained both goethite and lepidocrocite; however, transformation products of SchCa only contained goethite all along. Approximately 33.5% of the surface adsorbed-Ca was released into solution within 6 hr after Fe(II) injection. Aqueous Ca behaved in a "first release and then im-mobilization" manner, which indicated dissolution and secondary mineralization drove Ca migration during the Fe(II)-mediated transformation of SchCa. Adsorbed Ca blocked the surface sites for subsequent Fe(II) adsorption, limited the Fe(II)-Fe(III) ETAE, and decreased the transformation rates. This work sheds light on the complex geochemical behavior of schwertmannite under the influences of environmental perturbations in AMD environments.

Remediation performance and mechanisms of Cu and Cd contaminated water and soil using Mn/Al-layered double oxide-loaded biochar.

The combined pollution of heavy metals is ubiquitous worldwide. Mn/Al-layered double oxide-loaded crab shells biochar (LDO/BC) was prepared, so as to remediate the combined pollution of Cd and Cu in soil and water. The pristine and used LDO/BC were characterized and the results revealed that the layered double oxide was successfully loaded on crab shells biochar (BC) and metal element Ca in crab shells was beneficial to the formation of more regular layered and flake structure. The maximal adsorption capacity (Qm) of LDO/BC for aqueous Cu2+ and Cd2+ was 66.23 and 73.47 mg/g, respectively. LDO/BC and BC were used to remediate e-waste-contaminated soil for the first time and exhibited highly efficient performance. The extraction amount of Cu and Cd in the contaminated soil by diethylene triamine penta-acetic acid (DTPA) after treating with 5% LDO/BC was significantly reduced from 819.84 to 205.95 mg/kg (with passivation rate 74.8%) and 8.46 to 4.16 mg/kg (with passivation rate 50.8%), respectively, inferring that the bioavailability of heavy metals declined remarkably. The experimental result also suggested that after remediation by LDO/BC the exchangeable and weak acid soluble Cu and Cd in soil translated to reducible, residual and oxidizable fraction which are more stable state. Precipitation, complexation and ion exchange were proposed as the possible mechanisms for Cd and Cu removal. In general, these experiment results indicate that LDO/BC can be a potentially effective reagent for remediation of heavy metal contaminated water and soil.

Efficient removal of polybrominated diphenyl ethers from soil washing effluent by dummy molecular imprinted adsorbents: Selectivity and mechanisms.

Surfactant enhanced elution is an effective method for removing hydrophobic organic pollutants from soils. The key to the development of leaching technology is selective removal of targeted pollutants in soil washing effluent and recycling of surfactant solutions. In this study, a molecular imprinting technique was applied to selectively sorb polybrominated diphenyl ethers (PBDEs) in soil washing effluent. The novel molecular imprinted polymers (MIPs) using different template molecules were synthesized by precipitation polymerization. Adsorption behaviors and mechanisms of MIPs were studied through experiments and theoretical calculations. The results show that 4-bromo-4'-hydroxybiphenyl and toluene can be effective imprinting molecule for MIPs synthesis. The maximal adsorption capacity of selected dummy molecular imprinted polymer (D1-MIP) was 1032.36 µmol/g, and that of part molecular imprinted polymer (P-MIP) was 981.13 µmol/g. Their imprinting factors in 5 PBDEs adsorption ranged from 2.13 to 5.88, the recovery percentage of Triton X-100 can reach 99.09%, confirming the feasibility of reusing surfactant. Various PBDEs could be removed by MIPs, and Quantitative Structure Property Relationship analysis revealed that PBDEs' molecular volume, planarity, polarity, and hydrophobicity have major influences on their adsorption performance. DFT calculation revealed that Van der Waals force and hydrogen bonding played important roles during selective adsorption. These results can provide effective theoretical guidance for surfactant enhanced soil elution in practical engineering applications.

Remediation of Cu and As contaminated water and soil utilizing biochar supported layered double hydroxide: Mechanisms and soil environment altering.

Preparing materials for simultaneous remediation of anionic and cationic heavy metals contamination has always been the focus of research. Herein a biochar supported FeMnMg layered double hydroxide (LDH) composites (LB) for simultaneous remediation of copper and arsenic contamination in water and soil has been assembled by a facile co-precipitation approach. Both adsorption isotherm and kinetics studies of heavy metals removal by LB were applied to look into the adsorption performance of adsorbents in water. Moreover, the adsorption mechanisms of Cu and As by LB were investigated, showing that Cu in aqueous solution was removed by the isomorphic substitution, precipitation and electrostatic adsorption while As was removed by complexation. In addition, the availability of Cu and As in the soil incubation experiments was reduced by 35.54%-63.00% and 8.39%-29.04%, respectively by using LB. Meanwhile, the addition of LB increased the activities of urease and sucrase by 93.78%-374.35% and 84.35%-520.04%, respectively, of which 1% of the dosage was the best. A phenomenon was found that the richness and structure of microbial community became vigorous within 1% dosage of LB, which indirectly enhanced the passivation and stabilization of heavy metals. These results indicated that the soil environment was significantly improved by LB. This research demonstrates that LB would be an imaginably forceful material for the remediation of anionic and cationic heavy metals in contaminated water and soil.

Accumulation, transportation, and distribution of tetracycline and cadmium in rice.

Co-exposure to heavy metal and antibiotic pollution might result in complexation and synergistic interactions, affecting rice growth and further exacerbating pollutant enrichment. Therefore, our study sought to clarify the influence of different Tetracycline (TC) and Cadmium(Cd) concentration ratios (both alone and combined) on rice growth, pollutant accumulation, and transportation during the tillering stage in hydroponic system. Surprisingly, our findings indicated that the interaction between TC and Cd could alleviate the toxic effects of TC/Cd on aerial rice structures and decrease pollutant burdens during root elongation. In contrast, TC and Cd synergistically promoted the accumulation of TC/Cd in rice roots. However, their interaction increased the accumulation of TC in roots while decreasing the accumulation of Cd when the toxicant doses increased. The strong affinity of rice to Cd promoted its upward transport from the roots, whereas the toxic effects of TC reduced TC transport. Therefore, the combined toxicity of the two pollutants inhibited their upward transport. Additionally, a low concentration of TC promoted the accumulation of Cd in rice mainly in the root tip. Furthermore, a certain dose of TC promoted the upward migration of Cd from the root tip. Laser ablation-inductively coupled plasma mass spectrometry demonstrated that Cd mainly accumulated in the epidermis and stele of the root, whereas Fe mainly accumulated in the epidermis, which inhibited the absorption and accumulation of Cd by the rice roots through the generation of a Fe plaque. Our findings thus provide insights into the effects of TC and Cd co-exposure on rice growth.

[Exploration and practice on construction of Tibetan medicine prescription information database and knowledge discovery].

This study aimed to explore the underlying framework and data characteristics of Tibetan prescription information. The information on Tibetan medicine prescriptions was collected based on 11 Tibetan medicine classics, such as Four Medical Canons(Si Bu Yi Dian). The optimal classification method was used to summarize the information structure of Tibetan medicine prescriptions and sort out the key problems and solutions in data collection, standardization, translation, and analysis. A total of 11 316 prescriptions were collected, involving 139 011 entries and 63 567 pieces of efficacy information of drugs in prescriptions. The information on Tibe-tan medicine prescriptions could be summarized into a "seven-in-one" framework of "serial number-source-name-composition-efficacy-appendix-remarks" and 18 expansion layers, which contained all information related to the inheritance, processing, origin, dosage, semantics, etc. of prescriptions. Based on the framework, this study proposed a "historical timeline" method for mining the origin of prescription inheritance, a "one body and five layers" method for formulating prescription drug specifications, a "link-split-link" method for constructing efficacy information, and an advanced algorithm suitable for the research of Tibetan prescription knowledge discovery. Tibetan medicine prescriptions have obvious characteristics and advantages under the guidance of the theories of "three factors", "five sources", and "Ro-nus-zhu-rjes" of Tibetan medicine. Based on the characteristics of Tibetan medicine prescriptions, this study proposed a multi-level and multi-attribute underlying data architecture, providing new methods and models for the construction of Tibetan medicine prescription information database and knowledge discovery and improving the consistency and interoperability of Tibetan medicine prescription information with standards at all levels, which is expected to realize the "ancient and modern connection-cleaning up the source-data sharing", so as to promote the informatization and modernization research path of Tibetan medicine prescriptions.