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A nonparametric point-by-point (NPP) method is presented for high-accuracy measurement of the time-dependent frequency (laser frequency) in tunable laser absorption spectroscopy, crucial for ensuring ultimate measurement accuracy. In wavelength modulation spectroscopy in particular, the parametric methods in current use for time-dependent frequency measurement are insufficiently accurate and are difficult to apply to complex modulation scenarios. Based on a multi-scale viewpoint, point-by-point measurement of the frequency is realized by linear superposition of the frequency information mapped from the interferometric signal on a unit scale and on a local scale. Validation experiments indicate that the measurement accuracy of the proposed NPP method is three times that of the existing parametric methods, while effectively immunizing against non-ideal tuning effects. Additionally, the NPP method is suitable for use with arbitrarily complex modulations such as square wave modulation, for which parametric methods are inapplicable.
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The protein-polysaccharide nanofibers have attracted intensive attention in promoting wound healing, due to their components and nanoscale fibrous structure that mimics the native extracellular matrix (ECM). For the full-thickness wounds, in addition to promoting healing, hemostatic property and antibacterial activity are also of critical importance. However, currently, protein-polysaccharide-based nanofiber membranes exhibit poor mechanical properties, lack inherent hemostatic and antibacterial capabilities, as well as the ability to promote tissue repair. In this study, we developed composited membranes, which were composed of collagen (Col) and chitosan (Chs), through solvent alteration and post-processing, the membranes showed enhanced stability under physiological conditions, proper hydrophilic performance and improved mechanical property. Appropriated porosity and water vapor transmission rate, which benefit to wound healing, were detected among all the membranes except for Col membrane. Aimed at wound dressing, hemocompatibility, antibacterial activity and cell proliferation of the electrospun membranes were evaluated. The results indicated that the Col/Chs composited membranes exhibited superior blood clotting capacity, and the membranes with Chs exceeding 60% possessed sufficient antibacterial activity. Moreover, compared with Chs nanofibers, significant increase in cell grow was detected in Col/Chs (1:3) membrane. Taken together, the electrospun membrane with multiple properties favorable to wound healing, superior blood coagulation, sufficient antibacterial performance and promoting cell proliferation property make it favorable candidate for full-thickness skin wound healing.
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Antibacterianos , Materiales Biocompatibles , Proliferación Celular , Quitosano , Colágeno , Ensayo de Materiales , Membranas Artificiales , Nanofibras , Cicatrización de Heridas , Quitosano/química , Cicatrización de Heridas/efectos de los fármacos , Nanofibras/química , Colágeno/química , Antibacterianos/química , Antibacterianos/farmacología , Proliferación Celular/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Humanos , Vendajes , Animales , Porosidad , Coagulación Sanguínea/efectos de los fármacos , Ratones , Matriz Extracelular/metabolismoRESUMEN
Non-aqueous electrolytes, generally consisting of metal salts and solvating media, are indispensable elements for building rechargeable batteries. As the major sources of ionic charges, the intrinsic characters of salt anions are of particular importance in determining the fundamental properties of bulk electrolyte, as well as the features of the resulting electrode-electrolyte interphases/interfaces. To cope with the increasing demand for better rechargeable batteries requested by emerging application domains, the structural design and modifications of salt anions are highly desired. Here, salt anions for lithium and other monovalent (e.g., sodium and potassium) and multivalent (e.g., magnesium, calcium, zinc, and aluminum) rechargeable batteries are outlined. Fundamental considerations on the design of salt anions are provided, particularly involving specific requirements imposed by different cell chemistries. Historical evolution and possible synthetic methodologies for metal salts with representative salt anions are reviewed. Recent advances in tailoring the anionic structures for rechargeable batteries are scrutinized, and due attention is paid to the paradigm shift from liquid to solid electrolytes, from intercalation to conversion/alloying-type electrodes, from lithium to other kinds of rechargeable batteries. The remaining challenges and key research directions in the development of robust salt anions are also discussed.
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Sulfite-based advanced oxidation technology has received considerable attention for its application in organic pollutants elimination. However, the potential of natural sediments as effective catalysts for sulfite activation has been overlooked. This study investigates a novel process utilizing suspended sediment/sulfite (SS/S(IV)) for degradation of metronidazole (MNZ). Our results demonstrate that MNZ degradation efficiency can reach to 93.1 % within 90 min with 12.0 g SS and 2.0 mM sulfite. The influencing environmental factors, including initial pH, SS dosage, S(IV) concentration, temperature, and co-existing substances were systematically investigated. Quenching experiments and electron paramagnetic resonance analyses results indicate that SO3â¢- is the primary active substance responsible for MNZ degradation, with involvement of SO4â¢-, SO5â¢-, and â¢OH. X-ray photoelectron spectroscopy and Mössbauer spectra reveal that Fe (III)-silicates play a crucial role in activating S(IV). Furthermore, analysis of degradation intermediates and pathways of MNZ is conducted using liquid chromatography with mass spectrometry (LC -MS). The toxicity of MNZ and its intermediates were also systematically evaluated by the T.E.ST. program and wheat seeds germination test. This study offers valuable insight into the activation of sulfite by natural sediments and could contribute to the development of SS-based advanced oxidation processes (AOPs) for the in-situ remediation of antibiotics-contaminated water environments.
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Sedimentos Geológicos , Metronidazol , Ríos , Contaminantes Químicos del Agua , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Ríos/química , China , Oxidación-ReducciónRESUMEN
Indeed, tumors are a significant health concern worldwide, and understanding the underlying mechanisms of tumor development is crucial for effective prevention and treatment. Epigenetics, which refers to changes in gene expression that are not caused by alterations in the DNA sequence itself, plays a critical role in the entire process of tumor development. It goes without saying that the effect of methylation on tumors is a significant aspect of epigenetics. Among the methylation modifications, DNA methylation is an important part, which plays a regulatory role in tumor-related genes. Ten-eleven translocation 2 (TET2) is a highly influential protein involved in the modification of DNA methylation. Its primary role is associated with the suppression of tumor development, making it a significant player in cancer research. However, TET2 is frequently mentioned in hematological diseases, its role in solid tumors has received little attention. Studying the changes of TET2 in solid tumors and the regulatory mechanism will facilitate its investigation as a clinical target for targeted therapy and may also provide directions for clinical treatment of malignant tumors.
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Metilación de ADN , Proteínas de Unión al ADN , Dioxigenasas , Epigénesis Genética , Neoplasias , Proteínas Proto-Oncogénicas , Humanos , Neoplasias/genética , Neoplasias/terapia , Neoplasias/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genéticaRESUMEN
Background: Deposition of immune complexes drives podocyte injury acting in the initial phase of lupus nephritis (LN), a process mediated by B cell involvement. Accordingly, targeting B cell subsets represents a potential therapeutic approach for LN. Ginsenoside compound K (CK), a bioavailable component of ginseng, possesses nephritis benefits in lupus-prone mice; however, the underlying mechanisms involving B cell subpopulations remain elusive. Methods: Female MRL/lpr mice were administered CK (40 mg/kg) intragastrically for 10 weeks, followed by measurements of anti-dsDNA antibodies, inflammatory chemokines, and metabolite profiles on renal samples. Podocyte function and ultrastructure were detected. Publicly available single-cell RNA sequencing data and flow cytometry analysis were employed to investigate B cell subpopulations. Metabolomics analysis was adopted. SIRT1 and AMPK expression were analyzed by immunoblotting and immunofluorescence assays. Results: CK reduced proteinuria and protected podocyte ultrastructure in MRL/lpr mice by suppressing circulating anti-dsDNA antibodies and mitigating systemic inflammation. It activated B cell-specific SIRT1 and AMPK with Rhamnose accumulation, hindering the conversion of renal B cells into plasma cells. This cascade facilitated the resolution of local renal inflammation. CK facilitated the clearance of deposited immune complexes, thus reinstating podocyte morphology and mobility by normalizing the expression of nephrin and SYNPO. Conclusions: Our study reveals the synergistic interplay between SIRT1 and AMPK, orchestrating the restoration of renal B cell subsets. This process effectively mitigates immune complex deposition and preserves podocyte function. Accordingly, CK emerges as a promising therapeutic agent, potentially alleviating the hyperactivity of renal B cell subsets during LN.
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The minimization of irreversible active lithium loss stands as a pivotal concern in rechargeable lithium batteries, particularly in the context of grid-storage applications, where achieving the utmost energy density over prolonged cycling is imperative to meet stringent demands, notably in terms of life cost. Departing from conventional methodologies advocating electrode prelithiation and/or electrolyte additives, a new paradigm is proposed here: the integration of a designer lithium reservoir (DLR) featuring lithium orthosilicate (Li4SiO4) and elemental sulfur. This approach concurrently addresses active lithium consumption through solid electrolyte interphase (SEI) formation and mitigates minor yet continuous parasitic reactions at the electrode/electrolyte interface during extended cycling. The remarkable synergy between the Li-ion conductive Li4SiO4 and the SEI-favorable elemental sulfur enables customizable compensation kinetics for active lithium loss throughout continuous cycling. The introduction of a minute quantity of DLR (3 wt% Li4SiO4@S) yields outstanding cycling stability in a prototype pouch cell (graphite||LiFePO4) with an ampere-hour-level capacity (≈2.3 Ah), demonstrating remarkable capacity retention (≈95%) even after 3000 cycles. This utilization of a DLR is poised to expedite the development of enduring lithium batteries for grid-storage applications and stimulate the design of practical, implantable rechargeable batteries based on related cell chemistries.
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Indigenous medicinal plants with naturally inherited antimicrobial properties are promising sources of antimicrobial agents. Two indigenous Ethiopian traditional medicinal plants (Rhamnus prinoide and Croton macrostachyus) extracted using different solvents and the yield percentage, phytochemical analysis and antimicrobial activity of the plant extracts were examined and compared. The results of this study revealed that Rhamnus prinoide leaf extract using aqueous methanol/ethanol (1 : 1) had the highest yield (15.12 %), a minimum inhibitory concentration of 0.625â mg/mL, and a minimum bactericidal concentration of 10â mg/mL against S. aureus. Croton macrostachyus leaves showed a yield of 14.7 ±0.37 %, a minimum inhibitory concentration of 40â mg/mL, and a minimum bactericidal concentration of 40â mg/mL against S. aureus and E. coli. GC-MS analysis revealed that aqueous methanol/ethanol (1 : 1) of Rhamnus prinoide and Croton macrostachyus leaf extracts were composed of bioactive carbohydrates, flavonoid acid phenols, and terpenoids, while Croton macrostachyus extract contained primarily phytol (30.08 %). The presence of bioactive compounds confirms the traditional use of these plant leaves to treat various diseases, including wounds, leading to the conclusion that they could be applied to textiles for wound dressing in future studies.
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Antiinfecciosos , Plantas Medicinales , Plantas Medicinales/química , Metanol/química , Escherichia coli , Staphylococcus aureus , Bacterias , Antibacterianos/farmacología , Antibacterianos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Fitoquímicos/farmacología , Fitoquímicos/química , Antiinfecciosos/farmacología , EtanolRESUMEN
BACKGROUND: Currently, the mainstream treatments for systemic lupus erythematosus (SLE) are based on glucocorticoids and immunosuppressants, which are known to have considerable adverse effects. This meta-analysis is aimed at confirming the efficacy and safety of acupuncture therapy in combination with traditional medications in the treatment of SLE. METHODS: Multiple databases were searched for randomized controlled trials using acupuncture therapy in combination with conventional pharmacotherapy for the treatment of SLE, from the establishment of the database to March 2023. Study selection, data collection, as well as quality assessment were conducted by 2 reviewers independently. RevMan 5.4 and Stata 17 software were used for Meta-analysis. RESULTS: Seven eligible studies involving 514 patients with SLE were included. Meta-analysis demonstrated that in SLE patients, extra treatment with acupuncture was superior to drug therapy alone in improving the overall response rate (RR = 1.20, 95% confidence intervals [1.11, 1.29], P < .00001, heterogeneity P = .69, I2 = 0%) and regulating immunological indicators (C3, C4, IgG, T lymphocyte subpopulation, IL-6, ds-DNA, ESR) while reducing TCM symptom scores, the SLE Disease Activity Index (SLEDAI) and the incidence of adverse events on treatment (P ≤ 0.05). Additionally, it was able to reduce BUN, Scr and 24 hours urine protein, suggesting that acupuncture treatment had a protective effect on the kidneys. CONCLUSIONS: Acupuncture therapy combined with conventional pharmacotherapy is an efficient and safe way in the treatment of SLE. However, the conclusions drawn from this meta-analysis have some limitations due to the small number and uneven quality of the included studies, leading to heterogeneity and bias. Thus more relevant high-quality randomized controlled trials are needed for further evaluation in the future.
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Terapia por Acupuntura , Lupus Eritematoso Sistémico , Humanos , Terapia por Acupuntura/efectos adversos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/etiología , Inmunosupresores/uso terapéuticoRESUMEN
Silicon (Si)-based anodes are currently considered a feasible solution to improve the energy density of lithium-ion batteries owing to their sufficient specific capacity and natural abundance. However, Si-based anodes exhibit low electric conductivities and large volume changes during cycling, which could easily trigger continuous breakdown/reparation of the as-formed solid-electrolyte-interphase (SEI) layer, seriously hampering their practical application in current battery technology. To control the chemoelectrochemical instability of the conventional SEI layer, we herein propose the introduction of elemental sulfur into nonaqueous electrolytes, aiming to build a sulfur-mediated gradient interphase (SMGI) layer on Si-based anodes. The SMGI layer is generated through the domino reactions (i.e., electrochemical cascade reactions) involving the electrochemical reductions of elemental sulfur followed by nucleophilic substitutions of fluoroethylene carbonate, which endows the corresponding SEI layer with strong elasticity and chemomechanical stability and enables rapid transportation of Li+ ions. Consequently, the prototype Si||LiNi0.8Co0.1Mn0.1O2 cells attain a high-energy density of 622.2 W h kg-1 and a capacity retention of 88.8% after 100 cycles. Unlike previous attempts based on sophisticated chemical modifications of electrolyte components, this study opens a new avenue in interphase design for long-lived and high-energy rechargeable batteries.
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Before the debut of lithium-ion batteries (LIBs) in the commodity market, solid-state lithium metal batteries (SSLMBs) were considered promising high-energy electrochemical energy storage systems before being almost abandoned in the late 1980s because of safety concerns. However, after three decades of development, LIB technologies are now approaching their energy content and safety limits imposed by the rocking chair chemistry. These aspects are prompting the revival of research activities in SSLMB technologies at both academic and industrial levels. In this perspective article, we present a personal reflection on solid polymer electrolytes (SPEs), spanning from early development to their implementation in SSLMBs, highlighting key milestones. In particular, we discuss the SPEs' characteristics taking into account the concept of coupled and decoupled SPEs proposed by C. Austen Angell in the early 1990s. Possible remedies to improve the physicochemical and electrochemical properties of SPEs are also examined. With this article, we also aim to highlight the missing blocks in building ideal SSLMBs and stimulate research towards innovative electrolyte materials for future rechargeable high-energy batteries.
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BACKGROUND: Genistein (GEN) is one of the most well-known phytoestrogens identified in various legumes. Although increasing evidence shows GEN has a potential use in phytotherapy to regulate lipid metabolism, its therapeutic mechanisms have not yet been completely elucidated, especially epigenetic alterations of miRNAs to alleviate lipid accumulation in the liver remains unknown. PURPOSE: To clarify how GEN modulates the miRNA profile in HepG2 cells and investigate molecular mechanisms of the modulated miRNA on regulating hepatic lipid metabolism. METHODS: The miRNA microarray was performed to compare the miRNAs expression patterns, followed by determining principal miRNA and its target gene associated with hepatic lipid metabolism modulated by GEN. miR-363-3p mimics (mi) and phosphatase and tensin homolog (PTEN)-siRNA were transfected into HepG2 cells and GEN was further treated with the cells for 24 h RESULTS: GEN induced downregulation of miR-363-3p and upregulation of PTEN, which was a target mRNA of miR-363-3p. The miR-363-3p mi led to an upregulation of sterol-regulatory element-binding protein-1c (SREBP-1c) and its downstream lipid synthesis-related factors in HepG2 cells. In addition, the inhibition of PTEN led to an increase of lipogenesis, which was associated with the AKT/mTOR signal regulation. However, GEN treatment could abrogate the lipogenic effects of miR-363-3p mi or PTEN siRNA. The modulation was associated with estrogen receptor ß (ERß). CONCLUSION: We discerned a new mechanism that GEN regulated hepatic lipid metabolism by inhibiting miR-363-3p, which could be mediated via ERß and by targeting PTEN in HepG2 cells. Additionally, GEN reduced hepatic lipid accumulation by regulating PTEN-AKT/mTOR signal. It implicated a protective role of GEN by elucidating its epigenetic modification of the miRNA modulated by ERß on improving hepatic lipid metabolism and provided novel evidence of the mechanism on targeting miR-363-3p/PTEN in treating hepatic lipid disorders.
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Metabolismo de los Lípidos , MicroARNs , Humanos , Receptor beta de Estrógeno/genética , Receptor beta de Estrógeno/metabolismo , Transducción de Señal , Proteínas Proto-Oncogénicas c-akt/metabolismo , Genisteína/farmacología , Células Hep G2 , MicroARNs/genética , MicroARNs/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , ARN Interferente Pequeño/metabolismo , LípidosRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: The Aconitum genus plants as a natural pesticide for insecticide and rodent control has been recorded in Chinese folk. However, the insecticide effect, mechanism, and active composition of Aconitum polycarpum Chang ex W.T.Wang have not been studied further. AIM OF THE STUDY: This study was designed to analyze the chemical composition, evaluate contact toxicity of petroleum ether extracts (PEEs) and essential oils (EOs) of A. polycarpum, and further explore their possible insecticidal mechanism. MATERIALS AND METHODS: The roots of A. polycarpum were extracted with 90% methanol, and then extracted with petroleum ether to obtain PEEs; the EOs was extracted by distillation. The chemical compositions of PEEs and EOs were analyzed by GC-MS. Contact toxicity was evaluated by the immersion method. Exploring insecticidal mechanisms through in vitro enzyme inhibitory activity. RESULTS: 12 compounds were identified from PEEs by GC-MS, mainly including aliphatic (94.8%), the main compositions were Octadecadienol (ODO) (aliphatic, 53.2%) and L-Ascorbyl dipalmitate (LADP) (aliphatic, 36.1%). 24 compounds were identified in EOs. About 44.6% of the identified components were terpenoids and their derivatives, and the rest were mainly aliphatic (34.7%) and phenols (3.0%). The main chemical components were L (-)-Borneol (LB) (terpenoid, 28.3%), LADP (aliphatic, 19.1%), and Isoborneol (terpenoid, 9.1%). The contact toxicity indicated that the PEEs showed great contact toxicity against Spodoptera exigua (LC50â¯=â¯126.2â¯mg/L). Meanwhile, LADP (LC50â¯=â¯128.1â¯mg/L) and ODO (LC50â¯=â¯121.3â¯mg/L) was similar to that of Cyhalothrin (LC50â¯=â¯124.2â¯mg/L) in contact toxicity. In addition, we found that LADP and ODO exhibited excellent inhibitory activity against CarE (IC50â¯=â¯58.0, 56.1â¯mg/L, respectively) by measuring in vitro enzyme inhibitory activity, which was superior than Cyhalothrin (IC50â¯=â¯68.1â¯mg/L). CONCLUSIONS: The chemical compositions and contact toxicity of EOs and PEEs of A. polycarpum were analyzed and evaluated, and their insecticidal mechanisms were preliminarily discussed for the first time. It proved PEEs of A. polycarpum and its main components (LADP and ODO) exhibited excellent contact toxicity against S. exigua, and CarE was identified as a potential target for contact toxicity. This study indicated that the insecticidal activity of petroleum ether extracts from A. polycarpum is quite promising, and provides a practical and scientific basis for the development and application of botanical pesticides.
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Aconitum , Insecticidas , Aceites Volátiles , Insecticidas/farmacología , Aceites Volátiles/toxicidad , Aceites Volátiles/química , TerpenosRESUMEN
To analyze the molecular mechanism of Qinghao-Biejia (QH-BJ) drug pair in the treatment of systemic lupus erythematosus (SLE) based on the method of network pharmacology and molecular docking technology. The components and related targets of QH-BJ drug pair, as well as SLE-related targets, were obtained. Intersection targets of QH-BJ drug pair and SLE were screened to construct the protein-protein interaction network, conduct gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, and establish the component-target-pathway network. The core active components and core targets of QH-BJ drug pair for the treatment of SLE were selected, and molecular docking was carried out between the ligand components and the receptor target proteins. The core active components of QH-BJ drug pair for the treatment of SLE are luteolin, quercetin, and kaempferol; the core targets are PTGS2, HSP90AA1, RELA, MAPK1, MAPK14, AKT1, JUN, TNF, TP53. The ligand components can spontaneously bind to the receptor target proteins. Besides, QH-BJ drug pair is likely to act on PI3K/Akt signal pathway, interleukin-17 signal pathway, and TNF signal pathway in the treatment of SLE. The study indicates that QH-BJ drug pair might play a role in the treatment of SLE through multi-components, multi-targets, and multi-pathways.
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Artemisia annua , Medicamentos Herbarios Chinos , Lupus Eritematoso Sistémico , Humanos , Ligandos , Lupus Eritematoso Sistémico/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Farmacología en Red , Medicamentos Herbarios Chinos/uso terapéuticoRESUMEN
Zinc citrate (ZC) has been widely used in food as an important nutritional supplement. Accurate detection of ZC in food is important for health and safety. In this study, THz time-domain spectroscopy (THz-TDS) is used to quantitatively detect ZC in flour and milk powder mixtures. In our research, 15 different contents of ZC in flour and milk powder mixtures were prepared and measured by THz-TDS. A partial least squares (PLS) model was established based on the quantitative analysis of the absorption coefficient data of these two mixtures at 0.5-3.0 THz. The R2 and rms error (RMSE) given by the PLS model prediction were, respectively, 0.999 and 0.14% ZC in flour and 0.999 and 0.20% ZC in milk mixtures, indicating the predictions of the PLS model are in excellent agreement with the experimental measurements. The results show that combining THz-TDS with the PLS model can be used for accurate, quantitative analyses of ZC in food mixtures.
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Espectroscopía de Terahertz , Animales , Citratos , Harina , Leche , Polvos , Espectroscopía de Terahertz/métodos , ZincRESUMEN
Unrestricted reproduction and spread of pest had caused great damage to the quality and yield of crops in recent years. Besides the use of traditional chemical pesticides, natural products also make a huge contribution against pests. Chasmanthinine, a diterpenoid alkaloid isolated from Aconitum franchetii var. villosulum, shown extremely antifeedant activity against Spodoptera exigua. Therefore, a series of novel Chasmanthinine derivatives were synthesized and their biological activity was studied in this work. Compound 33 showed the strongest antifeedant activity (EC50 = 0.10 mg/cm2) among all the test compounds. The mechanism research of 33 revealed that its antifeedant effect was related to the inhibition of carboxylesterase (CES), and proved the thiophene acyl group could form a strong binding effect with CES by molecular docking. Moreover, compound 10 exhibited the strongest cytotoxicity (IC50 = 12.87 µM) against Sf9 cell line and moderate contact toxicity. The mechanism research indicated that compound 10 could induce Sf9 cells apoptosis. In summary, the results lay a foundation for the application of diterpene alkaloids in plant protection.
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Aconitum , Alcaloides , Insecticidas , Aconitum/química , Alcaloides/química , Animales , Insecticidas/farmacología , Simulación del Acoplamiento Molecular , SpodopteraRESUMEN
The increasing demand for high-energy powers have greatly incentivized the development of lithium carbon fluoride (Li||CFx ) cells. Five kinds of non-aqueous liquid electrolytes with various kinds of lithium salts (LiX, X=PF6 - , TFSI- , BF4 - , ClO4 - , and CF3 SO3 - ) were comparatively studied. Intriguingly, the LiBF4 -based electrolyte show relatively moderate ionic conductivities; yet, the corresponding Li||CFx cells deliver the highest discharge capacities among them. A combination of morphological and compositional analyses of the discharge CFx cathode suggest that the moderate donicity of BF4 - anion is accountable for favoring the breakdown of C-F bonds, and subsequently forming crystalline lithium fluoride as the main discharge products. This work brings not only fresh understanding on the role of salt anions for Li||CFx cells, but also inspire the electrolyte design for other conversion-type (sulfur and/or organosulfur) cathode materials desired for high-energy applications.
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Characterizing the permeability evolution and methane release is of great significance for the safe mining of the high gas outburst seams, as well as coal and gas simultaneous extraction. It contributes to reduce methane emissions from coal mining for greenhouse effect control. Theoretical analysis, laboratory testing, and numerical simulation are widely used methods to characterize the permeability and methane release with the treatment process of pressure-relief mining. However, these methods cannot fully reflect the complexity of filed practice. In this study, we report the effectiveness of protective coal seam (PCS) mining and the pressure-relief area in the protected coal seam (PDCS) based on detailed and integrated field measurements in a Chinese coal mine. To the best of our knowledge, it is the first time to measure the permeability coefficient and gas pressure evolution in the PDCS during the process of PCS longwall mining. The evolution of the permeability coefficient in the pressure-relief area during PCS mining can be divided into four stages: slowly decreasing, sharply increasing, gradually decreasing, and basically stable. The maximum permeability coefficient is 322 times of the initial value and stabilized at 100 times after the goaf compacted. The gas pressure evolution in the PDCS indicates that the strike pressure relief angle is 52.2° at the active longwall face zone, and 59.3° at the installation roadway side. The inclined pressure relief angles at the lower and upper sides of the longwall face are 75° and 78.9°, respectively. The residual gas content and gas pressure of the PDCS in the pressure-relief area are reduced to less than 6 m3/t and within 0.4 MPa, respectively. The field measurements further prove that pressure-relief mining can prevent coal and gas outbursts in PDCSs. The field observations in this paper can serve as benchmark evidence for theoretical analysis and numerical simulations, and also provide insights into realizing safety mining in similar conditions.
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Rechargeable lithium-based batteries built with high-energy anode materials (e.g., silicon-based and silicon-derivative materials) are considered a feasible solution to satisfy the stringent requirements imposed by emerging markets, including electric vehicles and grid storage, due to their higher energy density compared to contemporary lithium-ion batteries. The robustness of the solid electrolyte interphase (SEI) layer on high-energy anodes is critical to achieve long-term and stable cycling performances of the batteries. Herein, we propose a new type of designer cathode additive (DCA), i.e., an ultrathin coating layer of elemental sulfur on the cathode, for the in situ formation of a thin and robust SEI layer on various types of high-energy anodes. The DCA elemental sulfur undergoes simultaneous oxidation and reduction paths, forming lithium alkyl sulfate (R-OSO2OLi) and poly(ethylene oxide) (PEO)-like polymers on the anode surface. The as-formed R-OSO2OLi/PEO-modified SEI layer has good lithium cation (Li+) permeability to facilitate fast ion transportation across the interphases and superior elasticity to adapt to large volume changes, which is particularly effective for improving the cycling efficiency of high-energy anodes (e.g., ca. 14-35% increase in capacity retention for the silicon-carbon composite (SiC) or silicon-tin alloy (Si-Sn)||LiFePO4 cells). The present work opens a new avenue toward the practical deployment of high-energy rechargeable lithium-based batteries.
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Total petroleum hydrocarbon (TPH) contamination poses threats to ecological systems and human health. Many studies have reported its negative impacts on soil microbes, but limited information is known about microbial change and response to multiple TPH contamination events. In this study, we investigated TPH contamination level, microbial community structure and functional genes at a multi-contaminated industrial site in Lanzhou, where a benzene spill accident caused the drinking water crisis in 2014. TPHs distribution in soils and groundwater indicated multiple TPH contamination events in history, and identified the spill location where high TPH level (6549 mg kg-1) and high ratio of low-molecular-weight TPHs (>80%) were observed. In contrast, TPH level was moderate (349 mg kg-1) and the proportion of low-molecular-weight TPHs was 44% in soils with a long TPH contamination history. After the spill accident, soil bacterial communities became significant diverse (p = 0.047), but the dominant microbes remained the same as Pseudomonadaceae and Comamonadaceae. The abundance of hydrocarbon-degradation related genes increased by 10-1000 folds at the site where the spill accident occurred in multi-contaminated areas and was significantly related to 2-ring PAHs. Such changes of microbial community and hydrocarbon-degradation related genes together indicated the resilience of soil indigenous microbes toward multiple contamination events. Our results proved the significant change of bacterial community and huge shift of hydrocarbon-degradation related genes after the spill accident (multiple contamination events), and provided a deep insight into microbial response at industrial sites with a long period of contamination history.