Redox-neutral electrochemical decontamination of hypersaline wastewater with high technology readiness level.

Industrial hypersaline wastewaters contain diverse pollutants that harm the environment. Recovering clean water, alkali and acid from these wastewaters can promote circular economy and environmental protection. However, current electrochemical and advanced oxidation processes, which rely on hydroxyl radicals to degrade organic compounds, are inefficient and energy intensive. Here we report a flow-through redox-neutral electrochemical reactor (FRER) that effectively removes organic contaminants from hypersaline wastewaters via the chlorination-dehalogenation-hydroxylation route involving radical-radical cross-coupling. Bench-scale experiments demonstrate that the FRER achieves over 75% removal of total organic carbon across various compounds, and it maintains decontamination performance for over 360 h and continuously treats real hypersaline wastewaters for two months without corrosion. Integrating the FRER with electrodialysis reduces operating costs by 63.3% and CO2 emissions by 82.6% when compared with traditional multi-effect evaporation-crystallization techniques, placing our system at technology readiness levels of 7-8. The desalinated water, high-purity NaOH (>95%) and acid produced offset industrial production activities and thus support global sustainable development objectives.

A novel upregulated hsa_circ_0032746 regulates the oncogenesis of esophageal squamous cell carcinoma by regulating miR-4270/MCM3 axis.

INTRODUCTION: Circular RNAs (CircRNA) have emerged as an interest of research in recent years due to its regulatory role in various kinds of cancers of human body. Esophageal squamous cell carcinoma (ESCC) is one of the major disease subtype in Asian countries, including China. CircRNAs are formed by back-splicing covalently joined 3'- and 5'- ends rather than canonical splicing and are found to have binding affinity with miRNAs that conjointly contribute to oncogenesis. MATERIALS AND METHODS: 4 pairs of normal, cancer adjacent tissues and cancer tissues were analyzed by high-throughput RNA sequencing and 84 differentially upregulated circRNAs were detected in cancer tissues. hsa_circ_0032746 was silenced by siRNA and lentivirus and then further proliferation, migration and invasion were performed by CCK-8 and transwell assays. Bioinformatic analysis  predicted binding affinity of circRNA/miRNA/mRNA axis. RESULTS: After qPCR validation, we selected a novel upregulated hsa_circ_0032746 to explore its biogenetic functions which showed high expression in cancer tissues but not in cancer adjacent tissues. The clinicopathological relation of hsa_circ_0032746 showed positive correlation with the tumor location (P = 0.026) and gender (P = 0.05). We also predicted that hsa_circ_0032746 could sponge with microRNA. Bioinformatic analysis predicted 11 microRNA response element (MRE) sequences of hsa_circ_0032746 and dual luciferase reporter assay confirmed binding affinity with miR4270 evidencing further study of circRNA/miRNA role. The knockdown of hsa_circ_0032746 by siRNA and lentivirus demonstrated that proliferation, invasion and migration of ESCC were inhibited in vitro and vivo experiments. Bioinformatic analysis further predicted MCM3 as a target of miR-4270 and was found upregulated in ESCC upon validation. miR4270 mimic decreased the level of hsa_circ_0032746 and MCM3 while further rescue experiments demonstrated that hsa_circ_0032746 was dependent on miR4270/MCM3 axis on the development process of ESCC. CONCLUSION: We revealed for the first time that circ_0032746/mir4270/MCM3 contributes in proliferation, migration and invasion of ESCC and could have potential prognostic and therapeutic significance.

LINC01116 modulates EMT process via binding with AGO1 mRNA in oesophageal squamous cell carcinoma.

Recent researches have uncovered that long non-coding RNAs (lncRNAs) are closely correlated with the development of different diseases, while biological functions and hidden molecular mechanisms of antisense lncRNAs in oesophageal squamous cell carcinoma (OSCC) remain unclear. Here, we identified upregulation of LINC01116 in RNA sequencing data, online database, and in OSCC and intraepithelial neoplasia (IEN) specimens. Functionally, LINC01116 facilitates OSCC advancement and metastasis in vitro and vivo. Mechanistically, elevated expression of LINC01116 in OSCC cells other than tumor stroma and cytoplasmic enables it to activate AGO1 expression via complementary binding with AGO1 mRNA to facilitate EMT process of OSCC.

Detoxification and metabolism of glyphosate by a Pseudomonas sp. via biogenic manganese oxidation.

Biogenic manganese oxides (BMO) are widely distributed in groundwater and provides promise for adsorbing and oxidizing a wide range of micropollutants, however, the continuous biodegradation and bioavailability of micropollutants via cycle biogenic Mn(II) oxidation remains to be elucidated. In this study, glyphosate was degraded and to serve as the nutrient source by a Pseudomonas sp. QJX-1. The addition of glyphosate will not affect the Mn(II) oxidation function of the strain but will affect its Mn(II) oxidation process and effect. The glyphosate degradation products could further be used as the C, N and P sources for bacterium growth. Analysis of the RNA-seq data suggested that Mn(II) oxidation driven by oxidoreductases for glyphosate degradation. The long-term column experiments using biological Mn(II) cycling to realize continuous detoxification and metabolism of glyphosate, and thus revealed the synergism effects of biological and chemical conversion on toxic micropollutants and continuous metabolism in an aquatic ecosystem.

Decoding Single-cell Landscape and Intercellular Crosstalk in the Transplanted Liver.

BACKGROUND: Liver transplantation (LT) is the most effective treatment for various end-stage liver diseases. However, the cellular complexity and intercellular crosstalk of the transplanted liver have constrained analyses of graft reconstruction after LT. METHODS: We established an immune-tolerated orthotopic LT mouse model to understand the physiological process of graft recovery and intercellular crosstalk. We employed single-cell RNA sequencing and cytometry by time-of-flight to comprehensively reveal the cellular landscape. RESULTS: We identified an acute and stable phase during perioperative graft recovery. Using single-cell technology, we made detailed annotations of the cellular landscape of the transplanted liver and determined dynamic modifications of these cells during LT. We found that 96% of graft-derived immune cells were replaced by recipient-derived cells from the preoperative to the stable phase. However, CD206 + MerTK + macrophages and CD49a + CD49b - natural killer cells were composed of both graft and recipient sources even in the stable phase. Intriguingly, the transcriptional profiles of these populations exhibited tissue-resident characteristics, suggesting that recipient-derived macrophages and natural killer cells have the potential to differentiate into 'tissue-resident cells' after LT. Furthermore, we described the transcriptional characteristics of these populations and implicated their role in regulating the metabolic and immune remodeling of the transplanted liver. CONCLUSIONS: In summary, this study delineated a cell atlas (type-proportion-source-time) of the transplanted liver and shed light on the physiological process of graft reconstruction and graft-recipient crosstalk.

Pumping and sliding of droplets steered by a hydrogel pattern for atmospheric water harvesting.

Atmospheric water harvesting is an emerging strategy for decentralized and potable water supplies. However, water nucleation and microdroplet coalescence on condensing surfaces often result in surface flooding owing to the lack of a sufficient directional driving force for shedding. Herein, inspired by the fascinating properties of lizards and catfish, we present a condensing surface with engineered hydrogel patterns that enable rapid and sustainable water harvesting through the directional pumping and drag-reduced sliding of water droplets. The movement of microscale condensed droplets is synergistically driven by the surface energy gradient and difference in Laplace pressure induced by the arch hydrogel patterns. Meanwhile, the superhydrophilic hydrogel surface can strongly bond inner-layer water molecules to form a lubricant film that reduces drag and facilitates the sliding of droplets off the condensing surface. Thus, this strategy is promising for various water purification techniques based on liquid-vapor phase-change processes.

LncRNA SNHG16 promotes development of oesophageal squamous cell carcinoma by interacting with EIF4A3 and modulating RhoU mRNA stability.

BACKGROUND: Numerous studies have revealed that long noncoding RNAs (lncRNAs) are closely related to the development of many diseases and carcinogenesis. However, their specific biological function and molecular mechanism in oesophageal squamous cell carcinoma (ESCC) remains unclear. METHODS: RNA-Seq was performed to determine the differential expressions of lncRNAs in ESCC, and the level of SNHG16 expression was detected in ESCC and intraepithelial neoplasia (IEN) samples. In vitro and in vivo experiments were performed to explore the role of SNHG16 and the interaction of EIF4A3 and Ras homologue family member U (RhoU) signalling. RESULTS: One hundred and seventy-five upregulated and 134 downregulated lncRNAs were identified by RNA-Seq. SNHG16 was highly expressed in ESCC and intraepithelial neoplasia (IEN) samples, and its expression level was correlated with tumour differentiation and T stage. Overexpression of SNHG16 can facilitate ESCC cell proliferation and metastasis. Mechanistically, we noticed that SNHG16 could bind RNA binding protein (RBP)-eukaryotic translation initiation factor (EIF4A3) and interact with it to form a complex. Importantly, the coalition of SNHG16 and EIF4A3 ultimately regulated Ras homologue family member U (RhoU). SNHG16 modulated RhoU expression by recruiting EIF4A3 to regulate the stability of RhoU mRNA. Knockdown of RhoU further alleviated the effect of the SNHG16 oncogene in ESCC cells. CONCLUSIONS: The newly identified SNHG16-EIF4A3-RhoU signalling pathway directly coordinates the response in ESCC pathogenesis and suggests that SNHG16 is a promising target for potential ESCC treatment.

In Operando Visualization and Dynamic Manipulation of Electrochemical Processes at the Electrode-Solution Interface.

Revealing the dynamic processes at the electrode-solution interface is imperative for understanding electrochemical phenomena. Most techniques have been developed to sense the electrode surface changes at the nanoscale, but provide limited information on potential-induced interfacial ion redistribution at the mesoscale. Herein, we present an in operando visualization method utilizing a microfabricated electrochemical cell combined with a laser scanning confocal microscope to observe high-resolution and fast-response interfacial processes. We report potential-induced formation and transformation of the Nernst diffusion layer, demonstrating that pulsed voltage dynamically perturbs the interface and promotes ion diffusion. This provides an additional insight into developing a dynamic manipulation method to control the electrochemical process. Our novel visualization method can easily be applied to monitor different ionic behaviors in electrochemical reactions at the mesoscale.

Visualization of Electrochemically Accessible Sites in Flow-through Mode for Maximizing Available Active Area toward Superior Electrocatalytic Ammonia Oxidation.

Active chlorine species-mediated electrocatalytic oxidation is a promising strategy for ammonia removal in decentralized wastewater treatment. Flow-through electrodes (FTEs) provide an ideal platform for this strategy because of enhanced mass transport and sufficient electrochemically accessible sites. However, limited insight into spatial distribution of electrochemically accessible sites within FTEs inhibits the improvement of reactor efficiency and the reduction of FTE costs. Herein, a microfluidic-based electrochemical system is developed for the operando observation of microspatial reactions within pore channels, which reveals that reactions occur only in the surface layer of the electrode thickness. To further quantify the spatial distribution, finite element simulations demonstrate that over 75.0% of the current is accumulated in the 20.0% thickness of the electrode surface. Based on these findings, a gradient-coated method for the active layer was proposed and applied to a Ti/RuO2 porous electrode with an optimized pore diameter of ∼25 µm, whose electrochemically accessible surface area was 381.7 times that of the planar electrode while alleviating bubble entrapment. The optimized reactor enables complete ammonia removal with an energy consumption of 60.4 kWh kg-1 N, which was 24.2% and 39.9% less than those with pore diameters of ∼3 µm and ∼90 µm, respectively.

Macrophage GSK3ß-deficiency inhibits the progression of hepatocellular carcinoma and enhances the sensitivity of anti-PD1 immunotherapy.

BACKGROUND: Glycogen synthase kinase 3ß (GSK3ß) was originally discovered to regulate glycogen synthesis and show a relationship to tumors. However, the biological functions of GSK3ß in tumor-associated macrophages (TAMs) in cancers including hepatocellular carcinoma (HCC) remain unclear. METHODS: The enrichment of GSK3ß in tumor tissues was assessed by Gene Expression Omnibus (GEO) database. The in vitro and in vivo assays assisted in evaluating how GSK3ß in TAMs affected HCC in terms of proliferation, invasion and migration. Immunofluorescence was used to assess GSK3ß expression in TAMs in the anti-PD1 therapy non-responsive HCC group and the responsive group. Western blot and coimmunoprecipitation were performed to demonstrate the interaction between GSK3ß and PD-L1. We carried out in vivo experiments in a C57BL/6 mouse model of HCC established through subcutaneous injection. RESULTS: GEO single-cell RNA sequencing data suggested that GSK3ß was highly enriched in TAMs of HCC. According to in vitro and in vivo experiments, reducing GSK3ß in TAMs inhibits the cancer cell proliferation, invasion, and migration. The immunofluorescence and immunohistochemistry results confirmed that the GSK3ß is significantly upregulated in TAMs of the anti-PD1 therapy non-responsive group in comparison with the responsive group. In vitro and in vivo experiments confirmed that reduced GSK3ß in TAMs are capable of enhancing the sensitivity of anti-PD1 immunotherapy for HCC by decreasing PD-L1 ubiquitination. Mass spectrometry results suggested that high expression of CD14+GSK3ß+ in the peripheral blood mononuclear cell (PBMC) can predict non-responsive to anti-PD1 treatment. Moreover, escitalopram is confirmed to act as GSK3ß inhibitor that can increase the sensitivity of anti-PD1 immunotherapy for HCC. CONCLUSIONS: This study revealed that macrophage GSK3ß deficiency can inhibit the development of HCC by inhibiting the M2 phenotype and enhance the sensitivity of anti-PD1 immunotherapy for HCC by decreasing PD-L1 ubiquitination. The expression of CD14+GSK3ß+ in PBMC can noninvasively predict anti-PD1 sensitivity in HCC patients, which provides novel strategies to predict anti-PD1 sensitivity, increase anti-PD1 therapeutic effect, and bring new hope for HCC patients.

Peroral endoscopic myotomy treatment for symptomatic esophageal diverticulum: a systematic review and meta-analysis.

Peroral endoscopic myotomy (POEM) is a rapidly evolving technique for the treatment of esophageal diverticulum. The aim of this study was to perform a systematic review and meta-analysis of the literature focusing on POEM for symptomatic esophageal diverticula, including an in-depth evaluation of its efficacy, safety, and limitations. A comprehensive literature search was completed to identify articles that examined the efficacy and safety of POEM for esophageal diverticula. Heterogeneity among studies was assessed using the I2 statistic. Meta-regression and sensitivity analyses were performed to explore the sources of heterogeneity and assess potentially important covariates influencing the main outcomes. Primary endpoints such as rates of success, adverse events, and recurrences were evaluated. P values of ≤0.05 were considered statistically significant. Nine studies with a total of 153 patients were enrolled. Pooled technical success, clinical success, adverse events, and recurrence rates were 99% [95% confidence interval (CI), 97-100%; I2 = 0%), 94% (95% CI, 89-97%; I2 = 24%), 2% (95% CI, 0-6%, I2 = 0%), and 0% (95% CI, 0-1%; I2 = 0%), respectively. The pooled perforation rate was 6% (95% CI, 1-11%; I2 = 0%). Meta-regression analysis indicated that esophageal diverticula types and motility disorders were not associated with the clinical success rate (P > 0.05). POEM is a feasible, safe, and effective treatment for symptomatic esophageal diverticula, with low adverse events and recurrence rates.

Safety and efficacy of grazoprevir/elbasvir in the treatment of acute hepatitis C in hemodialysis patients.

Treatment of hepatitis C virus (HCV) infection with direct-acting antiviral agents (DAAs) in hemodialysis patients requires extensive consideration. At present, studies regarding DAAs for acute HCV infection in such patients are limited. The present study aims to evaluate the efficacy and safety of grazoprevir (GZR) plus elbasvir (EBR) treatment in acute hepatitis C (AHC) patients undergoing hemodialysis. Patients undergoing hemodialysis who had a nosocomial acute HCV infection were enrolled. All patients received GZR 100 mg/EBR 50 mg once daily for 12 weeks and were followed up for 12 weeks. Serum alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and HCV RNA levels were monitored during treatment and follow-up periods. Sustained virologic response at 12 weeks after treatment cessation and treatment-emergent adverse events (AEs) were assessed. A total of 68 AHC patients were enrolled. All patients were infected with HCV genotype 1b and achieved SVR12. Decreasing ALT, AST, and TBIL were observed over time in the first 4 weeks and became steady thereafter. Forty-eight (70.59%) patients reported at least one AEs. The most common AEs were fatigue, headache, and nausea. Two AHC patients discontinued treatment due to serious but drug-unrelated AEs. In conclusion, GZR/EBR has a high efficacy and safety profile in hemodialysis-dependent patients with genotype 1b AHC.

Measuring the elasticity of liquid-liquid phase separation droplets with biomembrane force probe.

Numerous biomacromolecules undergo liquid-liquid phase separation (LLPS) inside living cells and LLPS plays important roles in their functions. The droplets formed by LLPS molecules are complex fluids and their behavior follows fluid mechanics, thus studies on rheological and material properties are required to gain full insight into the biophysical mechanism of these droplets. Biophysical force spectroscopy techniques are particularly useful in this aspect. Indeed, atomic force microscopy and optical tweezers have been used to quantify the elasticity and the viscoelasticity of LLPS droplets. The Biomembrane Force Probe (BFP) is a single-molecule technique designed to investigate liquid-like objects and is more suitable to quantify the material properties of LLPS droplets, but its usage on LLPS droplets is not yet described. Here we present an experimental protocol to measure the Young's modulus of LLPS droplets using BFP, we believe that the application of BFP on phase separation studies can be expanded and will be very helpful in deciphering the underlying principles of LLPS.

Construction and Validation of an Immune-Related Gene Prognostic Index for Esophageal Squamous Cell Carcinoma.

Immune checkpoint inhibitor (ICI) therapy may benefit patients with advanced esophageal squamous cell carcinoma (ESCC); however, novel biomarkers are needed to help predict the response of patients to treatment. Differentially expressed immune-related genes within The Cancer Genome Atlas ESCC dataset were selected using the weighted gene coexpression network and lasso Cox regression analyses. Based on these data, an immune-related gene prognostic index (IRGPI) was constructed. The molecular characteristics of the different IRGPI subgroups were assessed using mutation information and gene set enrichment analysis. Differences in immune cell infiltration and the response to ICI therapy and other drugs were also analyzed. Additionally, tumor and adjacent control tissues were collected from six patients with ESCC and the expression of these genes was verified using real-time quantitative polymerase chain reaction. IRGPI was designed based on CLDN1, HCAR3, FNBP1L, and BRCA2, the expression of which was confirmed in ESCC samples. The prognosis of patients in the high-IRGPI group was poor, as verified using publicly available expression data. KMT2D mutations were more common in the high-IRGPI group. Enrichment analysis revealed an active immune response, and immune infiltration assessment showed that the high-IRGPI group had an increased infiltration degree of CD8 T cells, which contributed to the improved response to ICI treatment. Collectively, these data demonstrate that IRGPI is a robust biomarker for predicting the prognosis and response to therapy of patients with ESCC.

GdClean: removal of Gadolinium contamination in mass cytometry data.

MOTIVATION: Mass cytometry (Cytometry by Time-Of-Flight, CyTOF) is a single-cell technology that is able to quantify multiplex biomarker expressions and is commonly used in basic life science and translational research. However, the widely used Gadolinium (Gd)-based contrast agents (GBCAs) in magnetic resonance imaging (MRI) scanning in clinical practice can lead to signal contamination on the Gd channels in the CyTOF analysis. This Gd contamination greatly affects the characterization of the real signal from Gd-isotope-conjugated antibodies, severely impairing the CyTOF data quality and ruining downstream single-cell data interpretation. RESULTS: We first in-depth characterized the signals of Gd isotopes from a control sample that was not stained with Gd-labeled antibodies but was contaminated by Gd isotopes from GBCAs, and revealed the collinear intensity relationship across Gd contamination signals. We also found that the intensity ratios of detected Gd contamination signals to the reference Gd signal were highly correlated with the natural abundance ratios of corresponding Gd isotopes. We then developed a computational method named by GdClean to remove the Gd contamination signal at the single-cell level in the CyTOF data. We further demonstrated that the GdClean effectively cleaned up the Gd contamination signal while preserving the real Gd-labeled antibodies signal in Gd channels. All of these shed lights on the promising applications of the GdClean method in preprocessing CyTOF datasets for revealing the true single-cell information. AVAILABILITY AND IMPLEMENTATION: The R package GdClean is available on GitHub at https://github.com/JunweiLiu0208/GdClean. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Synergism of sweeping frequency ultrasound and deep eutectic solvents pretreatment for fractionation of sugarcane bagasse and enhancing enzymatic hydrolysis.

Sugarcane bagasse (SCB) is an abundant agricultural waste in China and the conversion of the waste into plethora of useful resources is very vital. To achieve this, fractionation of the waste is highly important in the biomass biorefinery. The present study aims at investigating the synergistic role of deep eutectic solvents (DES) with sweeping frequency ultrasound (SFUS) and fixed frequency ultrasound (FFUS) in the fractionation of SCB to enhance the enzymatic saccharification process. Therefore, the effects of ultrasound (US) and DES conditions on the pretreatment efficiency were investigated. Under optimum SCB pretreatment conditions, FFUS (40 kHz, 60 min) + DES (choline chloride (ChCl)-lactic acid (LA), 120 °C, 3 h) and SFUS (40 kHz, 60 min) + DES (ChCl-LA, 120 °C, 3 h), the lignin removal rates were 80.13 and 85.62%, respectively. The hemicellulose removal rates were 78.08 and 90.46%, respectively; and the contents of glucose, xylose and arabinose in the liquid fractions after FFUS + DES pretreatment were 7.07, 17.95 and 3.01%, respectively. However, the yield of glucose, xylose, and cellobiose after enzymatic hydrolysis of the SFUS + DES pretreated SCB were 86.76, 38.68, and 20.76%. Analytical studies revealed that the SFUS + DES pretreatment can effectively destroy the ultrastructure of SCB and reduce the crystallinity of cellulose. Furthermore, the mechanism of pretreatment with SFUS + DES was proposed, which confirmed the excellent performance of SFUS + DES. Thus, the application of SFUS + DES pretreatment was able to improve the removal of lignin and hemicellulose from SCBs.

Hot-Electron-Induced Photothermal Catalysis for Energy-Dependent Molecular Oxygen Activation.

Hot electrons activate reactants and reduce the activation energy barrier (Ea ) of a reaction through electron donation. However, a comprehensive understanding of the intrinsic driving force of this electron-donating effect is lacking, let alone the precise manipulation of electron donation processes. Herein, the essential and promotional role of hot electron energy on the electron-donating effect was elucidated using molecular oxygen activation (MOA) as a model reaction. Through providing an available electron source to the conventional photo-thermal conversion system, the high energy carried by hot electrons was liberated and greatly enhanced the electron donation towards the LUMO (π*) orbit of O2 . The energy was also transferred to O2 and elevated the potential energy surface (PES) of MOA, which was reflected by the enhanced formation of superoxide oxygen anions. As predicted, the Ea of MOA decreased by 45.1 % and exhibited a substantial light dependence, demonstrating that MOA became energy-efficient due to improved exploitation and conversion of photon energies.

Synergetic Lipid Extraction with Oxidative Damage Amplifies Cell-Membrane-Destructive Stresses and Enables Rapid Sterilization.

Here, we introduce an innovative "poison arrowhead" approach for disinfection based on a nanosheet bacterial inactivation system that acts synergistically to achieve sterilization rates of >99.99 % (Escherichia coli) over an ultrashort time period (≈0.5 min). The two-dimensional MoS2 "arrowhead" configuration has a sharp edge structure that enables the vigorous extraction of lipids from cell membranes and subsequent membrane disruptions. In the presence of permonosulfate, a strong oxidant, sulfur vacancies containing MoS2 activate the stable molecules, which in turn produce reactive oxygen species (ROS) from edge sites to basal areas. This process not only scavenges some portion of the phospholipids to allow for MoS2 surface refreshment but also directly attacks proteins thereby inflicting further damage to injured cells and amplifying the cell-membrane-destructive stresses toward pathogenic microorganisms. With small amounts of the new material, we successfully disinfected natural water (≈99.93 % inactivation in terms of total bacteria) within 30 s.

Multimode-ultrasound and microwave assisted natural ternary deep eutectic solvent sequential pretreatments for corn straw biomass deconstruction under mild conditions.

Mild and effective pretreatments are essential to deconstruct lignocellulosic biomass so as to reuse cellulose content for value-added products. In this study, sequential multimode-ultrasound and microwave with natural ternary deep eutectic solvent (NATDES) pretreatments were used to deconstruct corn straw and optimized factors such as NATDES, ultrasonic, and microwave parameters. Results indicated that the ultrasound-NATDES or microwave-NATDES pretreatment could remove 37.86% and 52.36% lignin, respectively. When using sequential multimode-ultrasound and microwave assisted NATDES pretreatment, the delignification efficiency increased to 61.50%, and the cellulose content increased from 34.70% to 76.08%. In addition, the delignification of sequential multimode-ultrasound and microwave assisted NATDES pretreatment (under the mild conditions of microwave heating at 60 °C and 60 min) increased to 57.39%, and the cellulose content increased to 59.98%, too. This highlighted the effect of the combined ultrasound and microwave technology. Finally, the microstructural changes of mercury intrusion porosimeters, scanning electron microscopy, thermogravimetric, X-ray diffraction and Fourier transform mid-infrared spectroscopy were conducted to confirm the effectiveness of this method to deconstruct corn straw. A mechanism of the deconstruction of corn straw biomass in NATDES with the assistance of the sequential multimode-ultrasound and microwave heating was proposed. This research could open a window for future use of biomass energy by deconstructing lignocellulosic biomasses using environmentally friendly pretreatment methods.

pH-Independent Production of Hydroxyl Radical from Atomic H*-Mediated Electrocatalytic H2O2 Reduction: A Green Fenton Process without Byproducts.

Hydroxyl radical (•OH) can hydroxylate or dehydrogenate organics without forming extra products and is thereby expediently applied in extensive domains. Although it can be efficiently produced through single-electron transfer from transition-metal-containing activators to hydrogen peroxide (H2O2), narrow applicable pH range, strict activator/H2O2 ratio requirement, and byproducts that are formed in the mixture with the background matrix necessitate the need for additional energy-intensive up/downstream treatments. Here, we show a green Fenton process in an electrochemical cell, where the electro-generated atomic H* on a Pd/graphite cathode enables the efficient conversion of H2O2 into •OH and subsequent degradation of organic pollutants (80% efficiency). Operando liquid time-of-fight secondary ion mass spectrometry verified that H2O2 activation takes place through a transition state of the Pd-H*-H2O2 adduct with a low reaction energy barrier of 0.92 eV, whereby the lone electron in atomic H* can readily cleave the peroxide bridge, with •OH and H2O as products (ΔGr = -1.344 eV). Using H+ or H2O as the resource, we demonstrate that the well-directed output of H* determines the pH-independent production of •OH for stable conversion of organic contaminants in wider pH ranges (3-12). The research pioneers a novel path for eliminating the restrictions that are historically challenging in the traditional Fenton process.