Acupressure: a possible therapeutic strategy for anxiety related to COVID-19: a meta-analysis of randomized controlled trials.

Background: From the end of 2019 to December 2023, the world grappled with the COVID-19 pandemic. The scope and ultimate repercussions of the pandemic on global health and well-being remained uncertain, ushering in a wave of fear, anxiety, and worry. This resulted in many individuals succumbing to fear and despair. Acupoint massage emerged as a safe and effective alternative therapy for anxiety relief. However, its efficacy was yet to be extensively backed by evidence-based medicine. This study aimed to enhance the clinical effectiveness of acupoint massage and extend its benefits to a wider population. It undertakes a systematic review of the existing randomized controlled trials (RCTs) assessing the impact of acupoint massage on anxiety treatment, discussing its potential benefits and implications. This research aims to furnish robust evidence supporting anxiety treatment strategies for patients afflicted with COVID-19 disease and spark new approaches to anxiety management. Objectives: This study evaluates the evidence derived from randomised controlled trials (RCTs), quantifies the impact of acupressure on anxiety manifestations within the general population, and proposes viable supplementary intervention strategies for managing COVID-19 related anxiety. Materials and methods: This review included RCTs published between February 2014 and July 2023, that compared the effects of acupressure with sham control in alleviating anxiety symptomatology as the outcome measure. The studies were sourced from the multiple databases, including CINAHL, EBM Reviews, Embase, Medline, PsycINFO, Scopus and Web of Science. A meta-analysis was performed on the eligible studies, and an overall effect size was computed specifically for the anxiety outcome. The Cochrane Collaboration Bias Risk Assessment Tool (RevMan V5.4) was employed to assess bias risk, data integration, meta-analysis, and subgroup analysis. The mean difference, standard mean deviation, and binary data were used to represent continuous outcomes. Results: Of 1,110 studies of potential relevance, 39 met the criteria for inclusion in the meta-analysis. The majority of the studies reported a positive effect of acupressure in assuaging anticipatory anxiety about treatment. Eighteen studies were evaluated using the STAI scale. The acupressure procedures were thoroughly documented, and studies exhibited a low risk of bias. The cumulative results of the 18 trials showcased a more substantial reduction in anxiety in the acupressure group compared to controls (SMD = -5.39, 95% CI -5.61 to -5.17, p < 0.01). A subsequent subgroup analysis, based on different interventions in the control group, demonstrated improvement in anxiety levels with sham acupressure in improving changes in anxiety levels (SMD -1.61, 95% CI: -2.34 to -0.87, p < 0.0001), and blank controls (SMD -0.92, 95% CI: -2.37 to 0.53, p = 0.22). Conclusion: In the clinical research of traditional Chinese medicine treatment of anxiety, acupressure demonstrated effectiveness in providing instant relief from anxiety related to multiple diseases with a medium effect size. Considering the increasing incidence of anxiety caused by long COVID, the widespread application of acupressure appears feasible. However, the results were inconsistent regarding improvements on physiological indicators, calling for more stringent reporting procedures, including allocation concealment, to solidify the findings.

Balancing Accuracy and Speed in Gaze-Touch Grid Menu Selection in AR via Mapping Sub-Menus to a Hand-Held Device.

Eye gaze can be a potentially fast and ergonomic method for target selection in augmented reality (AR). However, the eye-tracking accuracy of current consumer-level AR systems is limited. While state-of-the-art AR target selection techniques based on eye gaze and touch (gaze-touch), which follow the "eye gaze pre-selects, touch refines and confirms" mechanism, can significantly enhance selection accuracy, their selection speeds are usually compromised. To balance accuracy and speed in gaze-touch grid menu selection in AR, we propose the Hand-Held Sub-Menu (HHSM) technique.tou HHSM divides a grid menu into several sub-menus and maps the sub-menu pointed to by eye gaze onto the touchscreen of a hand-held device. To select a target item, the user first selects the sub-menu containing it via eye gaze and then confirms the selection on the touchscreen via a single touch action. We derived the HHSM technique's design space and investigated it through a series of empirical studies. Through an empirical study involving 24 participants recruited from a local university, we found that HHSM can effectively balance accuracy and speed in gaze-touch grid menu selection in AR. The error rate was approximately 2%, and the completion time per selection was around 0.93 s when participants used two thumbs to interact with the touchscreen, and approximately 1.1 s when they used only one finger.

Prediction of postoperative reintervention risk for uterine fibroids using clinical-imaging features and T2WI radiomics before high-intensity focused ultrasound ablation.

OBJECTIVE: To predict the risk of postoperative reintervention for uterine fibroids using clinical-imaging features and T2WI radiomics before high-intensity focused ultrasound (HIFU) ablation. METHODS: Among patients with uterine fibroids treated with HIFU from 2019 to 2021, 180 were selected per the inclusion and exclusion criteria (42 reintervention and 138 non-reintervention). All patients were randomly assigned to either the training (n = 125) or validation (n = 55) cohorts. Multivariate analysis was used to determine independent clinical-imaging features of reintervention risk. The Relief and LASSO algorithm were used to select optimal radiomics features. Random forest was used to construct the clinical-imaging model based on independent clinical-imaging features, the radiomics model based on optimal radiomics features, and the combined model incorporating the above features. An independent test cohort of 45 patients with uterine fibroids tested these models. The integrated discrimination index (IDI) was used to compare the discrimination performance of these models. RESULTS: Age (p < .001), fibroid volume (p = .001) and fibroid enhancement degree (p = .001) were identified as independent clinical-imaging features. The combined model had AUCs of 0.821 (95% CI: 0.712-0.931) and 0.818 (95% CI: 0.694-0.943) in the validation and independent test cohorts, respectively. The predictive performance of the combined model was 27.8% (independent test cohort, p < .001) and 29.5% (independent test cohort, p = .001) better than the clinical-imaging and radiomics models, respectively. CONCLUSION: The combined model can effectively predict the risk of postoperative reintervention for uterine fibroids before HIFU ablation. It is expected to help clinicians to develop accurate, personalized treatment and management plans. Future studies will need to be prospectively validated.

Potassium permanganate modification of hydrochar enhances sorption of Pb(II), Cu(II), and Cd(II).

Hydrochars formed by hydrothermal carbonization of hickory wood, bamboo, and wheat straw at 200 °C were modified by potassium permanganate (KMnO4) for the sorption of Pb(II), Cd(II), and Cu(II). The wheat straw hydrochar (WSHyC) modified with 0.2 M KMnO4 resulted in the most promising adsorbent (WSHyC-0.2KMnO4). Characterization of WSHyC and WSHyC-0.2KMnO4 revealed that the modified hydrochar features large specific surface area, rich of surface oxygenic functional groups (OCFG), and a significant amount of MnOx micro-particles. Batch adsorption experiments indicated that the adsorption rate by WSHyC-0.2KMnO4 was faster than for WSHyC, attaining equilibrium after around 5 h. The optimum adsorption capacity (Langmuir) of Pb(II), Cd(II), and Cu(II) by WSHyC-0.2KMnO4 was 189.24, 29.06 and 32.68 mg/g, respectively, 12 âˆ¼ 17 times greater than by WSHyC. The significantly enhanced heavy metal adsorption can be attributable to the increased OCFG and MnOx microparticles on the surface, thereby promoting ion exchange, electrostatic interactions, and complexation mechanisms.

Photoelectrochemical biosensor for DNA demethylase detection based on enzymatically induced double-stranded DNA digestion by endonuclease-exonuclease system and Bi4O5Br2-Au/CdS photoactive material.

A novel photoelectrochemical (PEC) biosensor for the detection of DNA demethylase MBD2 was developed based on Bi4O5Br2-Au/CdS photosensitive material. Bi4O5Br2 was firstly modified with gold nanoparticles (AuNPs), following with the modification onto the ITO electrode with CdS to realize the strong photocurrent response as a result of AuNPs had good conductibility and the matched energy between CdS and Bi4O5Br2. In the presence of MBD2, double-stranded DNA (dsDNA) on the electrode surface was demethylated, which triggered the digestion activity of endonuclease HpaII to cleave dsDNA and induced the further cleavage of the dsDNA fragment by exonuclease III (Exo III), causing the release of biotin labeled dsDNA and inhibiting the immobilization of streptavidin (SA) onto the electrode surface. As a results, the photocurrent was increased greatly. However, in the absence of MBD2, HpaII digestion activity was inhibited by DNA methylation modification, which further caused the failure in the release of biotin, leading to the successful immobilization of SA onto the electrode to realize a low photocurrent. The sensor had a detection of 0.3-200 ng/mL and a detection limit was 0.09 ng/mL (3σ). The applicability of this PEC strategy was assessed by studying the effect of environmental pollutants on MBD2 activity.

Antibody-free photoelectrochemical biosensor for DNA carboxylation detection based on SnS2@Ti3C2 heterojunction.

As an important epigenetic modification, 5-carboxycytosine (5caC) played an important role in gene regulation, cell differentiation and growth. 5caC existed in many cells and tissues, but it was highly similar to the structure of other cytosine derivatives and had less content in the genome. Therefore, it was urgent to develop a sensitive and highly selective trace biosensor to detect 5caC. A novel photoelectrochemical biosensor was fabricated for 5-carboxy-2'-deoxycytidine-5'-triphosphate (5cadCTP) detection, where SnS2@Ti3C2 nanocomposite was employed as photoactive material, polyethyleneimine was used as 5cadCTP recognition and capture reagent, and Ru(NH3)63+ was used as photosensitizer for signal amplification. Due the good conductivity of Ti3C2 MXene and the matched energy band between Ti3C2 MXene and SnS2, SnS2@Ti3C2 nanocomposite presented strong photoactivity, which was beneficial to the high detection sensitivity. For specific recognition of 5cadCTP, the covalent interaction of -NH2 in 5cadCTP with -COOH on the substrate electrode was used, which was beneficial to the high detection selectivity. A broad linear relationship between photocurrent and 5cadCTP concentration was observed ranging from 1 pM to 0.2 µM. The low detection limit of 260 fM was achieved. The developed method has high detection specificity and can even distinguish 5caC with its derivatives. In addition, the applicability was evaluated by detecting the content change of 5caC in the genomic DNA of rice seedlings after cultured with environmental pollutants. This work provides a novel platform for 5cadCTP detection, and it can also be applied to detect other cytosine derivatives with suitable recognition strategies.

Clinically ill patients' experiences of early mobilisation after liver transplantation: a qualitative study using Pender's health promotion model.

The aim of this study is to explore the factors influencing early mobilisation behaviours and patients' needs in critically ill patients after liver transplantation (LT). This interview study used phenomenological research, and Pender's health promotion model (HPM) was used to construct the interview guide. With the use of purposeful sampling, a total of 19 critically ill patients who experienced early mobilisation after LT were recruited at three tertiary hospitals in Beijing from August to November 2022. Data were collected through semi-structured interviews and analysed using Colaizzi's seven-step method. Nine themes were categorised into the three domains of Pender's HPM. The first domain was individual characteristics and experiences: (1) symptoms of end-stage liver disease limiting premobility behaviours and (2) previous treatment experience affecting understanding of early mobilisation after LT. The second domain was behaviour-specific cognition and affect: (3) coexistence of benefits and concerns in early mobilisation after LT, (4) barriers to early mobilisation after LT, (5) high self-efficacy in early mobilisation after LT, (6) individual differences in early mobilisation and (7) support and encouragement from family, wardmates and medical staff. The final domain was behavioural outcomes: (8) the need for sufficient staff, a quiet environment, safety, goals, guidance and family participation and (9) a strong willingness to comply with early mobilisation plans. The three areas and nine themes extracted in this study are helpful for the long-term development of early mobilisation in patients after LT.

Antibody-free photoelectrochemical strategy for simultaneous detection of methylated RNA, METTL3/METTL14 protein and MazF protein based on enhanced photoactivity of MoSe2-BiOI nanocomposite.

Taking advantages of the catalytic activity of METTL3/METTL14 protein towards adenine methylation in RNA sequence and the specific digestion activity of MazF protein towards unmethylated RNA sequence containing ACA bases, a novel photoelectrochemical biosensor was constructed for simultaneous detection of RNA methylation, METTL3/METTL14 protein and MazF protein. MoSe2-BiOI nanocomposite was prepared and considered as photoactive material, catalytic hairpin assembly strategy and in situ generation of electron donors catalyzed by polyaspartic acid-loaded alkaline phosphatase technique were employed as signal amplification. Under the optimum conditions, the detection ranges of methylated RNA, METTL3/METTL14 protein and MazF protein were 0.001-50 nM, 0.001-25 ng/µL, and 0.001-10 U/mL, respectively. The corresponding detection limits were 0.46 pM, 0.51 pg/µL and 0.42 U/µL with S/N = 3. In addition, the effect of drugs and composite pollutants on the activities of MazF proteins was assessed, proving the applicability of the developed method in the field of drug screening for MazF-related diseases. Moreover, the effects of pollutants on the activity of METTL3/METTL14 were also preliminarily explored, providing new information on pathogenic mechanism of pollutants.

Photoelectrochemical Biosensor for Histone Deacetylase Sirt1 Detection Based on Polyaspartic Acid-Engaged and Triggered Redox Cycling Amplification and Enhanced Photoactivity of BiVO4 by Gold Nanoparticles and SnS2.

A photoelectrochemical (PEC) biosensor was established for histone deacetylase Sirt1 detection based on the polyaspartic acid (PASP)-mediated redox cycling amplification and Sirt1 catalysis deacetylation-triggered recognition of the deacetylated substrate peptide, using PASP as the recognition reagent. After BiVO4 was composited with gold nanoparticles and SnS2, the photoactivity of the composite was greatly enhanced due to the matched energy band structure. Under the catalysis of Sirt1 enzyme, the acetylated substrate peptide was deacetylated to obtain a positive peptide, which was recognized by negative PASP. In addition to the recognition function, PASP also played other triple roles. First, PASP interacted with the positive peptide to form a double-stranded structure, which led to the electrode interface changing from irregular to regular, resulting in an improved PEC response. Second, PASP was involved into redox cycle amplification due to its reduction to dehydroascorbic acid. Further, it was used for repeated preparation of ascorbic acid to provide electron donors. This process enhanced the PEC response. Third, based on the matched energy band with BiVO4, PASP effectively improved the photoactivity of BiVO4. With multiplex signal amplification, the PEC biosensor showed a wide linear range (1.83-1830 pM) and high detection sensitivity with a low detection limit of 0.732 pM (S/N = 3). The applicability of this method was evaluated by studying the effects of a known inhibitor of nicotinamide and the heavy metal ions of Cd2+ and Pb2+ on Sirt1 enzyme activity, and the results showed that this method not only provided a new platform for screening Sirt1 enzyme inhibitors but also provided new biomarkers for evaluating the ecotoxicological effects of environmental pollutants.

MXene Enhanced Photoactivity of Bi2O3/Bi2S3 Heterojunction with G-wire Superstructure for Photoelectrochemical Detection of TET1 Protein.

Ten-eleven translocation 1 (TET1) protein has the potential to accelerate the oxygenation of 5-methylcytosine to 5-hydroxymethylcytosine (5hmC); then the -CH2OH of 5hmC can further covalently react with -SH catalyzed by M.HhaI methyltransferase. A brand-new photoelectrochemical (PEC) detection technique for the TET1 protein was created in light of this. For this objective, the Bi2O3/Bi2S3 heterojunction was first prepared by a one-pot hydrothermal method and served for photosensitive materials. For further enhancing the photoactivity, Bi2O3/Bi2S3 was blended with MXene to form an energy band-matched structure, thus improving the migration kinetics of photogenerated carriers. For achieving a high sensitivity of detection, a DNA Walker incorporated with the nicking endonuclease (Nb.BbvCI enzyme)-assisted signal amplification strategy was presented to output exponential G-quadruplex fragments. Self-assembly of the free G-quadruplex sequence into a G-wire superstructure with the assistance of Mg2+ provided more loading sites for MB and amplified the PEC signal. The linear range of the biosensor was 0.1-10 µg/mL with a detection limit of 0.024 µg/mL (S/N = 3) for TET1 protein under optimal experimental conditions. The suitability of the proposed method was evaluated by inhibitor screening experiments and the influence of environmental degradation on the activity of TET1 protein.

Three new and two newly recorded species of the water mite genus Arrenurus Dugs, 1834 (Acari, Hydrachnidia: Arrenuridae) from China.

This paper deals with five species of Arrenurus Dugs, 1834 from P. R. China. Arrenurus (Truncaturus) linguaus sp. nov., Arrenurus (Arrenurus) pseudodistinctus sp. nov. and Arrenurus (Arrenurus) yanchengensis sp. nov, are new to science; Arrenurus (Arrenurus) crassicaudatus Kramer, 1875 and Arrenurus (Megaluracarus) ussuriensis Sokolow, 1931 are recorded for the first time for the Chinese fauna. Arrenurus (Truncaturus) linguaus sp. nov. can be distinguished by tongue-shaped hyaline petiole, trapezoid hyaline membrane, and more or less triangular acetabular plates. Arrenurus (Arrenurus) pseudodistinctus sp. nov. can be distinguished by the median of petiole enlarged, obviously wider than the front and rear ends; ligulate process well-developed and fishtail-shaped; hyaline membrane trapezoid. Arrenurus (Arrenurus) yanchengensis sp. nov can be distinguished by a short hyaline membrane and extending to the base of the well-developed pygal lobes; petiole lobes have the same length as the petiole. Detailed descriptions and illustrations of the new and newly recorded species are given in this paper.

Fixed bed column performance of Al-modified biochar for the removal of sulfamethoxazole and sulfapyridine antibiotics from wastewater.

In this study, biochar derived from bamboo pretreated with aluminum salt was synthesized for the removal of two sulfonamide antibiotics, sulfamethoxazole (SMX) and sulfapyridine (SPY), from wastewater. Batch sorption experiments showed that Al-modified bamboo biochar (Al-BB-600) removed both sulfonamides effectively with the maximum sorption capacity of 1200-2200 mg/kg. The sorption mechanism was mainly controlled by hydrophobic, π-π, and electrostatic interactions. Fixed bed column experiments with Al-modified biochar packed in different dosages (250, 500 and 1000 mg) and flow rates (1, 2 and 4 mL/min) showed the dosage of 1000 mg and flow rate of 1 mL/min performed the best for the removal of both SMX and SPY from wastewater. Among the breakthrough (BT) models used to evaluate the fixed bed filtration performance of Al-BB-600, the Yan model best described the BT behavior of the two sulfonamides, suggesting that the adsorption process involved multiple rate-liming factors such as mass transfer at the solid surface and diffusion Additionally, the Bed Depth Service Time (BDST) model results indicated that Al-BB-600 can be efficiently used in fixed bed column for the removal of both SMX and SPY in scaled-up continuous wastewater flow operations. Therefore, Al-modified biochar can be considered a reliable sorbent in real-world application for the removal of SMX and SPY from wastewater.

Investigation of the effect of antibiotics on 5-formylcytosine content in mazie seedling tissues based on photoelectrochemical biosensor.

Given the improved photoactivity of Bi2S3 by MXene, an article photoelectrochemical biosensor was designed for 5-formyl-2'-deoxycytidine (5fdCTP) detection, where Bi2S3: MXene was selected as photoactive material, polydopamine was used as solid electron donor and 5fdCTP capture reagent, calcined ZIF-8(C-ZIF-8) was chosen as the artificial enzyme. With the catalyzed by C-ZIF-8, 4-chloro-1-naphthol was allegro oxidized by H2O2 to form the insoluble benzo-4-chlorohexadienone, and then deposited on the surface of the electrode, Resulting in a decrease of the PEC response. Under the optimum conditions, the sensor has a linear range of 0.001-200 nM and a detection limit of 0.51 pM (3σ). The suitability of the developed method was appraised by investigating the effect of antibiotics on 5fdCTP content in the genomic DNA of the roots of maize seedlings. As a new detection platform, the application of this approach can be expanded to investigative the impact of other pollutants on the content of 5fdCTP in plant or animal tissues, explore the feasibility of 5fdCTP as a new indicator for the ecotoxicological effect of pollutants, and the photoelectrochemical method as a new assessment technique for the ecotoxicological effects of pollutants.

Ball-milled bismuth oxybromide/biochar composites with enhanced removal of reactive red owing to the synergy between adsorption and photodegradation.

In this paper, bismuth oxybromide (BiOBr)/biochar composites were synthesized by a facile ball milling method for synergistic adsorption and photodegradation of Reactive red 120 (RR120). The characterizations show that ball milling changed the degree of crystallization, increased the surface area, and promoted the charge transfer ability of biochar. The 70% BiOBr/BC composite showed the best removal efficiency for RR120 removal with or without light illumination, which proves its enhanced removal ability by adsorption and photodegradation. The biochar is served as a support of BiOBr for preventing its aggregation and a transporter of charges for promoting the separation of photo-induced carriers in composites. BiOBr can release the adsorption sites on the surface of composites by degradation, which facilitated the RR120 removal and regenerated the photocatalyst for reusing. The strong interactions between BiOBr and biochar in composites resulted from ball milling were beneficial for the charge transfer and synergistic removal of adsorption and degradation. Findings of this work indicate that ball milling method is an effective method to prepare highly efficient biochar-based composites for RR120 removal through synergistic adsorption and photodegradation.

Vertical 1D/2D Heterojunction Architectures for Self-Powered Photodetection Application: GaN Nanorods Grown on Transition Metal Dichalcogenides.

Van der Waals (vdW) heterojunctions based on two-dimensional (2D) transition metal dichalcogenide (TMD) materials have attracted the attention of researchers to conduct fundamental investigations on emerging physical phenomena and expanding diverse nano-optoelectronic devices. Herein, the quasi-van der Waals epitaxial (QvdWE) growth of vertically aligned one-dimensional (1D) GaN nanorod arrays (NRAs) on TMDs/Si substrates is reported, and their vdW heterojunctions in the applications of high-performance self-powered photodetection are demonstrated accordingly. Such 1D/2D hybrid systems fully combine the advantages of the strong light absorption of 1D GaN nanoarrays and the excellent electrical properties of 2D TMD materials, boosting the photogenerated current density, which demonstrates a light on/off ratio above 105. The device exhibits a competitive photovoltaic photoresponsivity over 10 A W-1 under a weak detectable light signal without any external bias, which is attributed to the efficient photogenerated charge separation under the strong built-in potential from the type-II band alignment of GaN NRAs/TMDs. This work presents a QvdWE route to prepare 1D/2D heterostructures for the fabrication of self-powered photodetectors, which shows promising potentials for practical applications of space communications, sensing networks, and environmental monitoring.

Recovery of phosphorus from wastewater: A review based on current phosphorous removal technologies.

Phosphorus (P) as an essential nutrient for life sustains the productivity of food systems; yet misdirected P often accumulates in wastewater and triggers water eutrophication if not properly treated. Although technologies have been developed to remove P, little attention has been paid to the recovery of P from wastewater. This work provides a comprehensive review of the state-of-the-art P removal technologies in the science of wastewater treatment. Our analyses focus on the mechanisms, removal efficiencies, and recovery potential of four typical water and wastewater treatment processes including precipitation, biological treatment, membrane separation, and adsorption. The design principles, feasibility, operation parameters, and pros & cons of these technologies are analyzed and compared. Perspectives and future research of P removal and recovery are also proposed in the context of paradigm shift to sustainable water treatment technology.

Mechanisms and adsorption capacities of hydrogen peroxide modified ball milled biochar for the removal of methylene blue from aqueous solutions.

In this work, hickory chip biochars developed at distinctive pyrolysis temperatures were ball milled (BMHC) and then post-modified with a 10% hydrogen peroxide (H2O2) solution to obtain a set of novel sorbents (BMHC-H2O2). The specific surface area (SSA) was dramatically increased after ball-milling while the hydroxyl and carboxyl groups on the surface of the biochars were further increased through H2O2 modification. Additionally, thermal stability of the biochar treated with ball-milling was not greatly reduced by H2O2 modification and hydrodynamic radius was decreased. Ball milling enhanced the adsorption efficiency to methylene blue (MB) by the biochar, and this ability was further increased by H2O2 modification, because of the increasing in oxygen-containing functional groups (OCFG) to interact with MB. The rate of MB adsorption to BMHC-H2O2 was faster than that of BMHC, reaching equilibrium after about 6 h. Among adsorbents tested, the 450 °C BMHC-H2O2 had the greatest MB adsorption capacity (310 mg g-1).

P-enriched hydrochar for soil remediation: Synthesis, characterization, and lead stabilization.

One-step synthesis of multifunctional materials using biomass waste for environmental remediation is a current research hotspot. In this study, a novel P-enriched hydrochar was obtained by co-hydrothermal treatment of biomass (bamboo or hickory) with concentrated H3PO4 (biomass: H3PO4 = 1:4) at 200 °C for 7 h. The characteristics of the P-enriched hydrochar were determined and its effect on the stabilization of Pb in soils was investigated. Compared to pristine hydrochar, the weight yield of the P-enriched hydrochar was greater (by over 2 times). This was due to the enrichment of P (over 20% by weight), as the C, N, and H weight content was reduced. Moreover, the aromaticity, thermal stability, and surface functionality of P-enriched hydrochar were all higher than that of pristine hydrochar. Addition of the pristine hydrochar to a simulated 1300 mg·kg-1 Pb-contaminated soil at 3% (w/w) resulted in a 20%-40% reduction in leached Pb only after 4 weeks, compared to the control without hydrochar amendment. However, addition of the P-enriched hydrochar to the spiked Pb-contaminated soil reduced Pb leaching by about 60% after only 1 week and about 90% after 3 weeks. Besides, using a real Pb-contaminated soil (149,000 mg·kg-1 Pb), P-enriched hydrochar addition at 5% (w/w) resulted in a 100% decrease in Pb leaching in the first week and maintained leached Pb levels at <2 mg L-1, meeting U.S.-E.P.A. standards. Thus, P-enriched hydrochar stabilized Pb in both simulated and real Pb-contaminated soil quickly and efficiently. Hence, the potential of one-step co-hydrothermal carbonization of biomass with H3PO4 to produce a novel and sustainable P-enriched hydrochar with properties suitable for environmental remediation of cationic metals.

ZnO/biochar nanocomposites via solvent free ball milling for enhanced adsorption and photocatalytic degradation of methylene blue.

There are challenges in developing multifunctional materials that can not only effectively adsorb but also completely eliminate organic contaminants in water. In this work, novel ZnO/biochar nanocomposites were synthesized using a facile ball-milling method. A series of characterization results showed that the ZnO nanoparticles dispersed uniformly on carbon surface within the biochar matrix. Ball milling increased the mesopores and macropores of the nanocomposites by breaking biochar and squeezing ZnO. The addition of appropriate amount of ZnO into biochar enhanced both the adsorption capacity and photocatalytic ability of the nanocomposites for methylene blue (MB) removal. When the initial concentration of MB was 160 mg/g, the nanocomposites exhibited high MB removal efficiency (up to 95.19%) under visible light through the combination of adsorption and photocatalysis. This work provides a feasible synthesis of metal oxide/biochar nanocomposites with excellent adsorption and photocatalysis properties for the treatment of organic dye wastewater.

Ball milling biochar iron oxide composites for the removal of chromium (Cr(VI)) from water: Performance and mechanisms.

As the first of its kind, a novel biochar/iron oxide composite (BM-Fe-HC) was successfully prepared by simply ball milling iron-laden biochar (Fe-HC). The performance and mechanisms of Cr(VI) removal by BM-Fe-HC were investigated. Ball milling effectively reduced particle size, increased specific surface area, more importantly, enhanced the distribution and increased the exposure of iron oxides on biochar surface. As a result, Cr(VI) removal by BM-Fe-HC showed fast kinetics and large adsorption capacity with the Langmuir maximum capacity of 48.1 mg/g, higher than that of other biochar/iron composites reported in the literature. Acidic pH promoted Cr(VI) removal while competition ions (Cl-, SO42- and PO43-) inhibited Cr(VI) removal by BM-Fe-HC. Comparison of pre- and post-adsorption samples revealed that iron oxides of the BM-Fe-HC played the dominant role in the adsorption and reduction of Cr(VI) during the removal. After adsorption, part of adsorbed Cr(VI) was reduced by Fe(II) and then stabilized by Fe(III) in the form of amorphous CrxFe1-x(OH)3 on the composite surface. All the results demonstrate that novel ball-milled biochar/iron oxide composites can be used as an effective adsorbent to remove Cr(VI) from water.