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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. [ABSTRACT FROM AUTHOR]

This paper investigates global (long-time-averaged) and local (short-time-averaged) statistics in the near-field region of static-grid turbulence through wind tunnel experiments. Measurements are performed in the region x / M < 32 (where x is the streamwise distance from the grid and M is the mesh size of the grid) using hot-wire anemometry. Local statistics are calculated according to the methodology used in the previous time-dependent analysis [Zheng et al., "Unsteady dissipation scaling in static- and active-grid turbulence," J. Fluid Mech. 956, A20 (2023)]. The global dimensionless dissipation rate C ϵ exhibits a power-law decay with respect to the global turbulent Reynolds number R e λ and the global length scale ratio L / λ (where L is the integral length scale and λ is the Taylor microscale) is constant in the near-field region, consistent with previous studies on regular- and fractal-grid turbulence. The local dimensionless dissipation rate and the local length scale ratio also obey nonequilibrium scaling laws in both near- and far-field regions of grid turbulence when the turbulent Reynolds number is locally high, whereas the nonequilibrium scaling laws for the global statistics only hold in the near-field region. [ABSTRACT FROM AUTHOR]

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. P removal efficiencies and P recovery potential of four typical wastewater treatment processes are critically reviewed. Feasibility, transfer routes, operation parameters, and pros & cons of these technologies in P recovery are analyzed and compared P can be recovered from wastewater into value-added fertilizers or soil amendment. Perspectives and future research directions of P removal and recovery are outlined. [ABSTRACT FROM AUTHOR]

The paper deals with four new species of Arrenurus (Acari, Hydrachnidiae, Arrenuridae) from standing water habitats in China: Arrenurus (Arrenurus) pseudonemanisp. nov., Arrenurus (Arrenurus) circinatussp. nov., Arrenurus (Arrenurus) menglaensissp. nov., and Arrenurus (Megaluracarus) guantingensissp. nov. Arrenurus (Arrenurus) pseudonemanisp. nov. can be distinguished by the petiole membrane enlarged in the middle, making the middle part significantly wider than the front and rear ends. Arrenurus (Arrenurus) circinatussp. nov. can be distinguished by petiole bearing a circular petiole membrane at the end. Arrenurus (Arrenurus) menglaensissp. nov. can be distinguished by petiole with a pair of setae and split down the middle, forming a pair of pointed crescents at the ends. Arrenurus (Megaluracarus) guantingensissp. nov. can be distinguished cauda slightly convex basally, without lateral extensions, P-2 with 15 small medial setae near distoventral corner. All the type specimens are deposited in GUGC. [ABSTRACT FROM AUTHOR]

Arrenurus is considered one of the most specious genera of water mites. This paper deals with three species of Arrenurus Dugès, 1834 (Acari, Hydrachnidiae, Arrenuridae) from Delingha, Qinghai Province, PR China. Arrenurus (Arrenurus) jaggedis sp. nov. is new to science; Arrenurus (Arrenurus) affinis Koenike, 1887 and Arrenurus (Arrenurus) turgidus Koenike, 1911 are recorded for the first time for the Chinese fauna. Arrenurus (Arrenurus) jaggedis sp. nov. can be distinguished by the petiole with furrows at the end, lateral ridges jagged, dorsal humps well developed, the top sharp and curved towards the front edge of the body. Detailed descriptions and illustrations of the new and newly recorded species are given in this paper. [ABSTRACT FROM AUTHOR]

• Phosphates have been synthesized from bio-sourced phenols. • The phosphates are able to support iron, chromium and molybdenum to form catalysts. • The catalysts have 1,2 selectivity with adjustable syndiotacticity in 1,3-butadiene polymerization. Exploration of a versatile additive applicable to various metal catalysts for polymerization of 1,3-diene, unfortunately, has been unsuccessful due to the distinctive nature of metal centre. A novel class of phosphates derived from biosourced Guaiacol, p-Eugenol, Vanillin and Mequinol have been designed and synthesized in this work. These compounds can work well with iron, chromium and molybdenum catalysts as additive to actively catalyse butadiene polymerization. It has been revealed that the use of them is critically important to induce 1,2 enriched insertion along with a syndiotactic mode throughout the polymerization. An array of polybutadienes differs in not only the 1,2 incorporation, tacticity, but molecular weight, thus materials spanning from soft viscoelastic to tough elastomers and rigid plastics, have been obtained. It is rare that introduction of additive confers the catalysts so impressive performances simultaneously, including wider metal adaptability, high catalytic activity, mainly 1,2 regio- and tunable stereoselectivity, and strong thermal tolerance. DFT calculation is also carried out to shed light on the role of the ortho-positioned methoxyl moiety. [Display omitted] [ABSTRACT FROM AUTHOR]

Following the extensive researches of graphene, 2D layered semiconductors have attracted widespread attention for their intriguing physical properties. 2D α‐Ga2S3 as an important member of group IIIA–VIA semiconductors has outstanding optoelectronic properties. However, the controllable large‐size synthesis of ultrathin α‐Ga2S3 nanosheets still remains a huge challenge. In this paper, a large‐size ultrathin nanosheets of hexagonal Ga2S3 is prepared via an improved chemical vapor deposition method. High‐performance photodetectors based on the ultrathin Ga2S3 nanosheets is demonstrated. The device shows a high photosensitivity/detectivity (9.2 A W−1/1.4 × 1012 Jones) and a fast response time (rise/fall time of <4/3 ms), respectively. Strikingly, wearable flexible photodetectors based on Ga2S3 nanosheets are fabricated accordingly and demonstrate great response performance and stability. This work provides a new direction for 2D semiconductors to apply in next‐generation nanoscale smart optoelectronics. [ABSTRACT FROM AUTHOR]

• Fast and accurate prediction of high-resolution 3D air distribution are achieved. • The two ANNs respectively use one-step prediction and two-step prediction strategies. • Two-step prediction ANN could be helpful for improving prediction accuracy. • The method can be used for real-time HVAC control targeting occupant areas. To meet the thermal comfort requirements of room occupants, a fast and accurate method for predicting indoor high-resolution 3D airflow distribution is necessary, which can be combined with heating, ventilation, and air conditioning (HVAC) systems to adjust the indoor environment. Artificial neural networks (ANN) can establish complex mappings between variables with nonlinear relationships. The aim of this study was to verify the feasibility of an ANN for the fast and accurate prediction of indoor 3D airflow distribution. Considering two prediction strategies, ANN A and B were constructed. The inputs of both ANNs were the air supply velocity, air supply direction, and section location. ANN A output the airflow distribution of the entire room directly, whereas ANN B output the airflow distribution of the characteristic sections first and then the airflow distribution of other sections according to the contribution of the characteristic sections. The two ANNs' performances on training and testing datasets were compared. Both ANNs performed well in the training and interpolation cases. However, their performances decreased rapidly in the extrapolation cases. In the case of a large gap between the input and output dimensions of the ANNs, the two-step prediction strategy improved the prediction accuracy, accelerated convergence, and alleviated data imbalance problems. The prediction time of ANN A and B was 0.89 s and 12.38 s, respectively. The ANN can predict indoor high-resolution 3D airflow distribution quickly and accurately, and can add functions that include identifying internal heat sources and air supply inlet position changes. ANN combined with HVAC could allow real-time control to regulate indoor airflow. [ABSTRACT FROM AUTHOR]

Self‐powered UV photodetectors are highly desirable for applications in space communications and environmental monitoring. However, most self‐powered UV photodetectors exhibit unimpressive performance in weak signal detection. Herein, a self‐powered UV photodetector based on the core–shell GaN/MoO3–x nanorod array (NRA) heterojunction system is demonstrated. Homogeneous MoO3–x layers are deposited on GaN NRAs by a simple one‐step physical vapor deposition method. The photodetector device shows an ultrahigh specific detectivity of 2.7 × 1015 Jones at 355 nm without any power supply. Further analyses reveal a responsivity of 160 A W−1 and a high UV–vis rejection ratio (R355 nm/R400 nm) of 2.0 × 104 under zero bias. The self‐powered device also has a fast response speed with a rise/fall time of 73/90 µs. As a result, the self‐powered photodetector, featuring ultrahigh detectivity and responsivity along with fast response, exhibits great potential for applications in next‐generation UV detection. The core–shell NRA structure heterojunction design provides a valuable direction for realizing nanoscale self‐powered UV photodetectors. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A facile approach to prepare N-doped carbon materials was developed. • N-doped biochar was synthesized by simply ball milling pristine biochar with NH 3 ·H 2 O. • NH 2 and C N were loaded on biochar through the dehydration of COOH and OH. • N-doped biochar showed enhanced sorption for CO 2 and reactive red in comparison to N-free biochar. Abstract Doping of nitrogen (N) on carbon materials often requires complicated synthetic steps or specific machinery. In this study, N-doped biochar was successfully synthesized by simply ball milling pristine biochar with ammonium hydroxide. The content and species of N in the resulting N-doped biochars were carefully characterized, the formation mechanisms of N-related groups were illustrated, and their applications in CO 2 uptake and reactive red removal were evaluated. Most of N introduced to biochar was loaded on its surface in forms of NH 2 and C N, resulting from the dehydration of COOH and OH. Biochars produced at 450 °C were doped with more N on the surface (XPS, 2.41%–2.65%) than those produced at 600 °C (XPS, 1.18%–1.82%) because the content of O-containing functional groups in biochar decreases with increasing pyrolysis temperature. The basic properties of N-related groups enhanced the sorption performance of biochar to both acidic CO 2 and anionic reactive red. For example, the CO 2 uptake of the N-doped, 450 °C hickory biochar was 31.6%–55.2% higher than the corresponding pristine and ball-milled biochars. The maximum sorption capacity of the N-doped, 600 °C bagasse biochar to reactive red was about 3.66–16.2 times of the corresponding biochars without N doping. This paper provides an alternative and facile approach to prepare N-doped biochar that can be extended to other carbon materials to meet the specific needs in different applications, especially adsorption. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Engineered biochar showed strong batch adsorption ability to P in real secondary treated wastewater. • Engineered biochar in fixed-bed columns also effectively removed P from the wastewater. • Commonly used fixed-bed dynamic adsorption models describe the P breakthrough curves well. • Exhaust P-laden biochar promoted mung bean seed germination and seedling growth. Abstract Phosphorus (P), a vital growth-limiting nutrient, is often lost in wastewater discharge, which may not only deteriorate water quality but also accelerate P depletion. In this study, laboratory experiments were conducted to investigate the reclamation and reuse of P from secondary treated wastewater (STWW) by engineered biochar loaded with aluminum oxyhydroxides (AlOOH). Biochar loaded with colloidal and nanosized AlOOH crystalline flakes was successfully produced through direct pyrolysis of hickory wood chips pretreated with aluminum salt. STWW samples were collected from a local wastewater treatment plant to evaluate the P sorption ability of the engineered biochar. The real wastewater was used in batch sorption experiments and the results showed that the engineered biochar effectively removed P from the STWW with relatively fast kinetics (<8 h) and good capacity (8,346 mg-P/kg), mainly through the electrostatic attraction mechanism. When the engineered biochar was packed in fixed-bed columns, it also effective removed P from the real STWW. The P removal efficiencies of the fixed-bed columns were affected by biochar dosage and flow rate. Various fixed-bed filtration models were applied to simulate the column experimental data and the model results matched the experimental breakthrough curves of P well. After the use, the engineered biochar was laden with P and thus significantly stimulated seed (Vigna radiata R. Wilczek) germination and early seedling growth. Findings from this study demonstrate that engineered biochar has promising applications in wastewater treatment because it can not only reduce P level in discharge to benefit the environment but also reclaim it as an agricultural fertilizer to improve P biogeochemical cycling and sustainability. [ABSTRACT FROM AUTHOR]

The epitaxial structures of GaN films grown on AlN/Al heterostructures by pulsed laser deposition (PLD) are designed with and without an amorphous AlN layer, and quality-enhanced crack-free GaN epitaxial films are obtained. Compared with GaN epitaxial films grown without inserting the amorphous AlN layer, by inserting a ∼5 nm-thick amorphous AlN layer in GaN, the residual stress in ∼600 nm-thick GaN epitaxial films is greatly reduced from −0.81 to −0.19 GPa, and high-density dislocations are annihilated in the amorphous AlN layer. The full-width at half-maximum for GaN(0002) and GaN(10-12) decreases from 1.1° and 1.2° to 0.90° and 0.98°, respectively. The root-mean-square surface roughness of as-grown GaN epitaxial films is also decreased from 3.5 to 1.5 nm. Evidently, the amorphous AlN layer can release the stress and trap the dislocations, preventing them from extending into the upper layer, as well as improve the surface morphology of GaN epitaxial films. Moreover, the nucleation mechanism of dislocation formation and annihilation in GaN epitaxial films grown on AlN/Al heterostructures by PLD with an amorphous AlN layer is hence proposed. These quality-enhanced GaN epitaxial films are of paramount importance for the application of GaN-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

High-quality AlN epitaxial films have been epitaxially grown on Cu(111) substrates by pulsed laser deposition (PLD) through effectively controlling the interfacial reactions between AlN epitaxial films and Cu substrates. The interfacial properties of the as-grown AlN/Cu hetero-interfaces and their formation mechanisms have been systemically studied. A 2.1 nm-thick CuxAl1−xN interfacial layer is formed in AlN/Cu hetero-structures at a high growth temperature of 600 °C, while abrupt and sharp AlN/Cu hetero-interfaces with no interfacial layer are achieved by effectively controlling the interfacial reactions at a low growth temperature of 450 °C. The as-grown ∼300 nm-thick AlN epitaxial films grown at 450 °C show very smooth surfaces with a root-mean-square surface roughness of 1.2 nm and high crystalline quality with full-width at half-maximum values of X-ray rocking curves for AlN(0002) and AlN(10−12) of 0.7° and 0.8°, respectively. Meanwhile, the residual stress in the as-grown AlN epitaxial films is also well controlled through low temperature growth with a residual compressive stress of 0.30 GPa. These high-quality AlN epitaxial films are of paramount importance for the commercial development of high-performance AlN-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

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 SnS 2 @Ti 3 C 2 nanocomposite was employed as photoactive material, polyethyleneimine was used as 5cadCTP recognition and capture reagent, and Ru(NH 3) 6 3+ was used as photosensitizer for signal amplification. Due the good conductivity of Ti 3 C 2 MXene and the matched energy band between Ti 3 C 2 MXene and SnS 2 , SnS 2 @Ti 3 C 2 nanocomposite presented strong photoactivity, which was beneficial to the high detection sensitivity. For specific recognition of 5cadCTP, the covalent interaction of –NH 2 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. [Display omitted] • Ti 3 C 2 /SnS 2 heterojunction materials was prepared with good photoelectric activity. • As a sensitizer, Ru(NH 3) 6 3+ extended the spectral response of Ti 3 C 2 /SnS 2 , thus improving the visible light utilization. • A novel photoelectrochemical biosensor was constructed for DNA carboxylation detection. • The effect of environmental pollutants on DNA carboxylation in rice seedlings was investigated. [ABSTRACT FROM AUTHOR]

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. MoSe 2 –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. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The CS-AgBr greatly improves the photoelectric activity of Bi 2 S 3. • N6-methyladenosine-5′-triphosphate was specifically recognized and detected by PEC biosensor. • The photocurrent response is enhanced by the band matching of Bi 2 S 3 /CS-AgBr/CeO 2. • The effect of three antibiotics on m6ATP expression in rice seedlings was investigated. CS-AgBr and octahedral CeO 2 greatly enhanced the photoactivity of Bi 2 S 3 nanoflowers due to the Bi 2 S 3 can form an energy band match with CS-AgBr and CeO 2 , which can accelerate electron transfer and reduce photogenerated electron-hole pair recombination. Thus, CeO 2 /CS-AgBr/Bi 2 S 3 exhibits good photoelectrochemical (PEC) response. With this as a basis, a novel PEC immunosensor was intended for N6-methyladenosine-5′-triphosphate (m6ATP) detection, in which m6ATP antibody was applied as the recognition unit for m6ATP, Bi 2 S 3 /CS-AgBr was utilized towards the photoactive material, and CeO 2 was employed as the signal amplification unit. m6ATP antibody was firstly captured on CPBA/CS-AgBr/Bi 2 S 3 /ITO surface through the covalent reaction between the boronic acid group of 4-carboxyphenylboronic acid (CPBA) and the o-diol structure of m6ATP antibody. Then, m6ATP was specifically recognized based on the specific immune reaction between the antigen and the antibody. Finally, signaling amplification unit of CeO 2 achieved signal enhancement through the capture of the phosphate group of m6ATP. Under optimal conditions, the PEC biosensor exhibited a wide linear range of 0.001–150 nM and a low detection limit of 0.48 pM (3σ). The suitability was assessed by investigating the results of the effect of antibiotics on the m6A levels in total RNA of rice root and leaf tissues. The results indicated that all of the three antibiotics (tobramycin, amoxicillin and chloramphenicol) inhibited the expression of m6ATP within 1, 4 and 7 days of cultivation. [ABSTRACT FROM AUTHOR]

Given the improved photoactivity of Bi 2 S 3 by MXene, an article photoelectrochemical biosensor was designed for 5-formyl-2′-deoxycytidine (5fdCTP) detection, where Bi 2 S 3 : 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 H 2 O 2 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. [Display omitted] • The accordion-like MXene greatly improves the photoelectric activity of Bi 2 S 3. • The effect of antibiotics on 5fC expression in maize seedlings was investigated. • 5fC was detected by photoelectrochemical method using Bi 2 S 3 /MXene as photoactive material. • 5fC was recognized by PDA and C-ZIF-8 was used as photoelectrochemical signal inhibitor. [ABSTRACT FROM AUTHOR]

The Yao'an gold deposit is located in the middle of the Jinshajiang-Ailaoshan alkali-rich metallogenic belt, and this belt hosts many porphyry-type Cu-Au-Mo deposits formed at 46–33 Ma. Yao'an porphyry gold-mineralization is intimately associated with biotite syenite porphyry, whereas the contemporaneous quartz syenite porphyry is barren. In this study, we compared the major and trace elements of apatite and zircon and isotopic compositions of zircon from the biotite syenite porphyry and quartz syenite porphyry, to explore their geochemical differences that may affect their mineralization potential. The results show that both porphyries were derived from the partial melting of the thickened lower crust, which has been modified by slab-derived fluids, but has different mineral crystallization sequences, magma fluid activities, and magma oxidation states, respectively. REE contents in apatite and zircon can be used to reveal the crystallization sequence of minerals. A rapid decrease of (La/Yb)N ratio in apatite from both porphyries may be caused by the crystallization of allanite. Large variation of Cl contents and negative correlation between F/Cl and (La/Yb)N in apatite from fertile porphyry indicate that it has experienced the exsolution of Cl-bearing hydrothermal fluid. Higher Y/Ho and lower Zr/Hf in zircon from fertile porphyry indicate a stronger fluid activity than barren porphyry. The high S, V, As contents, δEu, low δCe in apatite, as well as high Ce4+/Ce3+ and log(fO2) estimated from zircon geochemistry from fertile porphyry, indicate high a oxidation state of fertile porphyry, similar to other fertile porphyries in this metallogenic belt. High fluid activity and fluid exsolution are conducive to the migration and enrichment of metal elements, which are very important for mineralization. High oxygen fugacity inhibits the precipitation of metal in the form of sulfide, thereby enhancing the mineralization potential of rock. Therefore, the exsolution of Cl-bearing hydrothermal fluid and high oxygen fugacity are the key factors promoting mineralization in Yao'an area. [ABSTRACT FROM AUTHOR]

[Display omitted] • H 2 O 2 -modified ball-milled biochar were synthesized to adsorb methylene blue (MB). • H 2 O 2 modification increased the oxygen-containing functional groups of biochar. • H 2 O 2 modification improved the adsorption capacity of biochar to MB. In this work, hickory chip biochars developed at distinctive pyrolysis temperatures were ball milled (BMHC) and then post-modified with a 10% hydrogen peroxide (H 2 O 2) solution to obtain a set of novel sorbents (BMHC-H 2 O 2). 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 H 2 O 2 modification. Additionally, thermal stability of the biochar treated with ball-milling was not greatly reduced by H 2 O 2 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 H 2 O 2 modification, because of the increasing in oxygen-containing functional groups (OCFG) to interact with MB. The rate of MB adsorption to BMHC-H 2 O 2 was faster than that of BMHC, reaching equilibrium after about 6 h. Among adsorbents tested, the 450 °C BMHC-H 2 O 2 had the greatest MB adsorption capacity (310 mg g−1). [ABSTRACT FROM AUTHOR]

Engineered biochars (EBCs) loaded with metal oxides/hydroxides have been used as sorbents to remove and recycle phosphate (P) from wastewater. However, P removal by EBCs made with different types and loading of metals have rarely been compared in a single study. Thus, in this study, EBCs were synthesized through pyrolysis of bamboo or hickory wood chips (25 g) pretreated with four amounts (25, 50, 75, and 100 mmol) of magnesium (Mg), aluminum (Al), or iron (Fe) salt solutions (Mg-EBC, Al-EBC, and Fe-EBC, respectively). The resulting EBCs were loaded with metal oxides/hydroxides that served as P adsorption sites. Al-EBCs showed the highest aqueous stability with little metal dissolution, which can be attributed to the low level of residual (unconverted) metal salt as well as the extremely low solubility of loaded Al metal oxyhydroxide. After the leaching/washing, the metal loading efficiencies of the Al- and Mg-EBCs were similar (50–60%) and stable metal loadings increased with pretreatment salt amounts, indicating that the amount of the two metal oxides/hydroxides in the EBCs can be controlled during pretreatment. However, stable iron oxide on the Fe-EBCs remained almost the same for all the four levels of pretreatment, reflecting saturation of the biochar surface. All the EBCs showed increasing P adsorption with increasing metal loading. At low initial P concentrations of 31 mg/L, Fe- and Al-EBCs removed up to 68% and 94% of P, likely through an electrostatic interaction mechanism. At high P concentrations, Mg-EBC had the largest P adsorption capacity (119.6 mg P/g), mainly through the combination of surface precipitation and electrostatic interaction mechanisms. This study demonstrates that metal oxide/hydroxide-loaded EBCs are promising sorbents that can be designed to meet specific needs for the removal of aqueous P in various applications. Unlabelled Image • Engineered biochars (EBCs) were produced from two feedstock with different loadings of metals. • EBCs presented increasing P adsorption with increasing metal loadings. • Mg-EBC showed the largest P adsorption capacity (119.6 mg P/g). • Al-EBCs showed the highest aqueous stability with little metal dissolution. • Metal-loaded EBCs are promising sorbents for environmental applications. [ABSTRACT FROM AUTHOR]

Self‐powered photodetectors have paved the way for electronic applications in fields such as civilian communication, infrared mapping, and industrial automatic control. However, most self‐powered photodetectors have faced photoresponse‐speed and device‐scale bottlenecks. Herein, a novel, self‐powered detector with an ultrafast response speed based on a core–shell InN/In2S3 nanorod array is proposed. A wafer‐scale InN/In2S3 nanorod array with good homogeneity is synthesized on Si substrates via a simple two‐step method involving molecular beam epitaxy and chemical vapor deposition. The photodetector device exhibits excellent self‐powered properties and a high current on/off ratio of 5 × 103. Further analyses determined that the device have an excellent photovoltaic responsivity and detectivity of 140 mA·W−1 and 4.0 × 1010 Jones, respectively (0 V). Impressively, the device exhibits an ultrafast photoresponse with a rise/fall time of 22/32 µs. The self‐powered InN/In2S3 photodetector with an ultrafast response speed shows superior potential for electronic applications. The core–shell nanostructure hybrid heterojunction introduces a novel idea for wafer‐scale nano‐photodetectors. [ABSTRACT FROM AUTHOR]

A facile ball-milling method was developed to synthesize MgO/biochar nanocomposites as a dual-functional adsorbent. The physicochemical properties of the synthesized nanocomposites indicated that the composites achieved nano-scaled morphologies and mesoporous structure with MgO nanoparticles, which is approximate 20 nm and dispersed uniformly on the surface of the biochar matrix. Batch sorption experiments yielded 62.9% removal of phosphate, an anion, and 87.5% removal of methylene blue, a cationic organic dye, at low adsorbent dosages of 1.0 g L−1 and 0.2 g L−1, respectively. This work indicates that ball milling, as a facile and promising method for synthesis of carbon-metal oxide nanocomposites, lends the advantage of operational flexibility and chemical adjustability for targeted remediation of diverse environmental pollutants. Image 1 • Solvent-free synthesis of MgO/biochar nanocomposites was achieved through ball milling. • MgO nanoparticles (20 nm) dispersed uniformly on the surface of the biochar matrix. • MgO/biochar nanocomposites showed dual functions to effectively adsorb cationic dye and anionic phosphate. • Ball milling method has the advantage of operational flexibility and chemical adjustability. [ABSTRACT FROM AUTHOR]

The anisotropy of GaN(11-20) makes it possible to fabricate polarized ultraviolet (UV) photodetectors (PDs) for applications in fields such as remote sensing and airborne astronomical navigation. The defect density has a significant effect on the performance of GaN(11-20)-based UV PDs. However, the mechanism through which different defects and their densities affect the performance of these devices is unclear. Therefore, in this work, we investigated the mechanisms of the screw or mixed dislocation, edge dislocation, and basal stacking fault (BSF) densities affecting the dark current, responsivity, and response time of GaN (11-20)-based PDs, respectively. We observed that the screw or mixed dislocation increased the dark current mainly through reducing the Schottky barrier height and forming leakage current, whereas the edge dislocation and BSF decreased the responsivity by reducing the electron mobility. Furthermore, all the three types of defects increased the response time through forming traps to recombine the holes with electrons and thus delaying the escape of carriers. These results are highly significant for developing nonpolar GaN-based UV PDs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Wheat straw hydrochar modified with 0.2 M KMnO 4 obtained optimal results. • KMnO 4 modification loaded MnOx microparticles on hydrochar surface. • Oxygen-containing surface functional groups increased after modification. • KMnO 4 modification enhanced adsorption of Pb(II), Cd(II), Cu(II) by > 10 times. Hydrochars formed by hydrothermal carbonization of hickory wood, bamboo, and wheat straw at 200 °C were modified by potassium permanganate (KMnO 4) for the sorption of Pb(II), Cd(II), and Cu(II). The wheat straw hydrochar (WSHyC) modified with 0.2 M KMnO 4 resulted in the most promising adsorbent (WSHyC-0.2KMnO 4). Characterization of WSHyC and WSHyC-0.2KMnO 4 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-0.2KMnO 4 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-0.2KMnO 4 was 189.24, 29.06 and 32.68 mg/g, respectively, 12 ∼ 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. [ABSTRACT FROM AUTHOR]

Graphic abstract Highlights • Governing adsorption mechanisms of heavy metals onto carbon adsorbents are summarized. • Various methods for introduction of oxygen, nitrogen, and sulfur functional groups onto carbon surfaces are categorized. • Effects of various functional groups on heavy metal adsorption onto different carbon materials are discussed. • Perspectives of future work on functionalized carbon adsorbents for heavy metal removal is also presented. Abstract Carbon-based adsorbents such as graphene and its derivatives, carbon nanotubes, activated carbon, and biochar are often used to remove heavy metals from aqueous solutions. One of the important aspects of effective carbon adsorbents for heavy metals is their tunable surface functional groups. To promote the applications of functionalized carbon adsorbents in heavy metal removal, a systematic documentation of their syntheses and interactions with metals in aqueous solution is crucial. This work provides a comprehensive review of recent research on various carbon adsorbents in terms of their surface functional groups and the associated removal behaviors and performances to heavy metals in aqueous solutions. The governing removal mechanisms of carbon adsorbents to aqueous heavy metals are first outlined with a special focus on the roles of surface functional groups. It then summarizes and categorizes various synthesis methods that are commonly used to introduce heteroatoms, primarily oxygen, nitrogen, and sulfur, onto carbon surfaces for enhanced surface functionalities and sorptive properties to heavy metals in aqueous solutions. After that, the effects of various functional groups on adsorption behaviors of heavy metals onto the functionalized carbon adsorbents are elucidated. A perspective of future work on functional carbon adsorbents for heavy metal removal as well as other potential applications is also presented at the end. [ABSTRACT FROM AUTHOR]

Novel graphitic carbon nitride nanocones (g-CNNCs) were synthesized for the first time in this study. The SEM, TEM, XPS and FT–IR were used to research the structure of the g-CNNCs. We found that the g-CNNCs showed high selective and sensitive for fluorescence enhancement detection of Pb2+ ion via covalent interaction. In addition, the g-CNNCs exhibit stable and specific concentration-dependent fluorescence intensity in the presence of Pb2+ ion in the range of 1–200 μmol·dm−3, and the limit of detection was estimated to be 0.0438 μmol·dm−3 (3S/k). More importantly, the g-CNNCs were used to detect practical samples with satisfactory results. Schematic illustration of graphitic carbon nitride nanocones fluorescence enhanced sensing Pb2+ ion. Unlabelled Image • Graphitic carbon nitride nanocones (g-CNNCs) were synthesized for the first time. • Pb2+ ion can enhance g-CNNCs fluorescence intensity. • g-CNNCs displayed excellent selectivity and sensitivity for lead ion. • g-CNNCs were used to detect lead ion with high accuracy comparing with AAS. [ABSTRACT FROM AUTHOR]

Performance-improved vertical GaN-based light-emitting diodes (LEDs) have been fabricated on Si substrates through designing the epitaxial structures with a combination of an AlN interlayer and a SiNx interlayer. The AlN interlayer is used to introduce more compressive stress in GaN epitaxial films to balance the tensile stress formed in thick n-GaN epitaxial films from cracking, and the SiNx interlayer is employed to annihilate the dislocation density to improve the crystalline quality of GaN epitaxial films. By using the optimized epitaxial structures, high-quality crack-free GaN-based LED wafers have been obtained. The full-widths at half-maximum from the GaN(0002) and GaN(10−12) X-ray rocking curves are as small as 280 arcsec and 310 arcsec, respectively. The hetero-interfaces of the InGaN/GaN multiple quantum wells are sharp and abrupt. After the LED wafers are fabricated into vertical LED chips, they reveal high-performance with a high light output power of 595 mW and a small working voltage of 2.75 V with an electroluminescence dominant wavelength of 456 nm @ 350 mA, corresponding to a wall-plug efficiency (WPE) as high as 61.8%. These performance-improved vertical LED chips open a broad prospect in the application of high-end lighting applications. [ABSTRACT FROM AUTHOR]

The anisotropic surface etching behavior of nonpolar a-plane GaN (112̅0) epitaxial films, grown by pulsed laser deposition, was investigated experimentally by wet chemical etching. Crystal-orientation dependent face state, induced by anisotropic growth kinetics, is the origination of the anisotropic properties of the a-plane GaN epitaxial films. Defects that propagate into the surface offer initial positions for the etching process. A joint effect of two factors determines the etching-exposed surface morphology, primarily including triangular prisms and pits, thus making wet chemical etching a promising tool for the investigation of defect distribution. Type I1 basal stacking faults and partial dislocations are proven to have a direct connection with etching-exposed triangular prisms and pits, respectively. This study presents a mechanism research from the standpoint of the evolution process of the surface morphology during the etching process and brings insight for further understanding of the anisotropic properties of the nonpolar GaN epitaxial films for the realization of a high polarization light-emission device, which has a broad application in display and backlighting. [ABSTRACT FROM AUTHOR]

Drought conditions and nutrients loss have serious impacts on soil quality as well as crop yields in agroecosystems. New techniques are needed to carry out effective soil water and nutrient conservation and fertilizer application tools. Here, calcium alginate (CA) beads impregnated with ball-milled biochar (BMB) were investigated as a new type of water/nutrients retention agent. Both CA and Ca-alginate/ball milled biochar composite (CA-BMB) beads showed high kinetic swelling ratios in KNO 3 solution and low kinetic swelling ratios in water, indicating that CA-BMB beads have the potential to retain mineral nitrogen and nutrients by ion exchange. Pseudo-second-order kinetic model well-described the swelling kinetics of both beads in KNO 3 solution. Over a range of temperatures, the characteristics of dehydration suggested that impregnation with BMB improved the water holding capacity and postponed the dehydration time of Ca-alginate. The cumulative swelling and release characteristics of water, K + , and NO 3 − indicated that CA-BMB beads have great potential as a soil amendment to improve its nutrient retention and water holding capacity. [ABSTRACT FROM AUTHOR]

AlN/nitrided sapphire and AlN/non-nitrided sapphire hetero-structures epitaxially grown by pulsed laser deposition (PLD) have been carried out. The characterizations find that when the nitridation process is implemented on sapphire substrates, the properties of AlN/sapphire hetero-structures are improved significantly. It is also identified that very smooth AlN surface with the root-mean-square surface roughness of 1.5 nm, full-width at half-maximums for AlN(0002) and AlN(10–12) X-ray rocking curves of 0.59°and 0.91°. Abrupt AlN/sapphire hetero-interfaces are obtained in AlN/nitrided sapphire hetero-structures. These high-quality AlN/nitrided sapphire hetero-structures shed light for the fabrication of highly-efficient AlN/nitrided sapphire-based devices. [ABSTRACT FROM AUTHOR]

To predict the risk of postoperative reintervention for uterine fibroids using clinical-imaging features and T2WI radiomics before high-intensity focused ultrasound (HIFU) ablation. 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. 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. 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. [ABSTRACT FROM AUTHOR]

Understanding the effects of environmental pollutants on RNA methylation and its relative enzymatic activity can provide new markers for the evaluation of the ecotoxicological effects of environmental pollutants. To achieve this aim, sensitive and selective detection technique for m6A and its relative enzyme is necessary. Herein, an antibody-free enzyme-assisted photoelectrochemical (PEC) biosensor for detection of m6A and fat mass and obesity-associated protein (FTO) was constructed based on enzymatic m6A structural change, where Se-MoSe 2 nanoflower was selected as the photoactive material, gold nanoparticles (AuNPs) was used as recognition reagent, dm6AMP (N6-dithiolsitolmethyladenosine monophosphate, product of enzymatic m6A structural change and RNA hydrolysis) was used as the target molecule, and ZnSe was employed as signal amplification unit with the matched energy bandgap with Se-MoSe 2 nanoflower. This biosensor can simultaneously identify m6AMP and FTO protein with high sensitivity and specificity. The effect of three kinds of antibiotics (Griseofulvin, sulfadiazine, lincomycin) on the content of m6A in the total RNA of the roots and leaves of rice seedlings were firstly investigated using PEC technique. Then, the effect of four heavy metals (AsO 4 3-, Cd2+, Hg2+, Pb2+) on FTO protein activity was investigated with the IC 50 value of 43.61, 55.58, 50.48 and 35.99 μg/L, respectively. [Display omitted] • Photoactivity of MoSe 2 was improved by Se and ZnSe. • The mechanism for the increased photoactivty was investigated. • An antibody-free PEC biosensor was constructed based on Se-MoSe 2 and ZnSe. • The detection limits were 6.3 pM for m6A RNA and 0.78 ng/L for FTO. • The effect of heavy metal ions on FTO oxidation activity was assessed [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) photodetection has been of great importance in the fields of aerospace, space communications, and remotely sensed images. However, conventional UV photodetectors (PDs) have been facing intrinsic drawbacks of complicate structural issues and interference from ambient visible light. Therefore, wide bandgap semiconductors have attracted significant attention. Herein, self-powered PDs based on the monolithic germanium disulfide (m-GeS2)/gallium nitride (GaN) pn heterojunction have been proposed with a large-size m-GeS2 over 2 cm2. The electronic and optical properties of the m-GeS2/GaN heterojunction are investigated via experiments and first-principles methods. The PDs reveal an impressive performance in self-powered response and high responsivity and detectivity of 16.8 mA W−1 and 1.03 × 1011 Jones, respectively. Further analyses determined that the PDs show an ultrafast photoresponse with a rise and fall time of < 0.30 and 1.10 ms at 365 nm. Consequently, this study provides a feasible method for the synthesis of large-sized m-GeS2 and demonstrates its enormous potential in high-performance, self-powered UV photodetection. [ABSTRACT FROM AUTHOR]

[Display omitted] • More studies of MPs in soils and groundwater are needed in South America, Africa, and Oceania. • Soil migration and wastewater effluents may be the potential sources and pathways of MP contamination in groundwater. • Most MPs negatively affect soil properties, animals, and plants. • Humans may expose to antibiotic resistance genes through exposure to MP-polluted soils and groundwater. Microplastic (MP) pollution has raised public concerns in recent decades globally due to its wide global spreading and potential toxicity. Most of existing studies have focused on MP pollution in marine, freshwater, and sediment systems. However, much less research attention has been paid to soil, which is a major sink of MPs. Furthermore, research interest in MPs in groundwater is even lower than that in soils. There is a critical need to digest and summarize the existing knowledge and the latest advancements to promote research on MP pollution in soils and groundwater. As the first of its kind, this work provides a systematical review of the newest knowledge on occurrences, sources, analytical methods, and impacts of MPs in both soils and groundwater. It first outlines the characteristics (global occurrences, sources, and pathways) of MP pollution in soils and groundwater. Commonly used analytical methods including sample collection (sites, tools, depth, points, and quantity), sample preparation (drying and sieving), extraction (separation, digestion, etc.), identification (visual sorting, chromatography, and vibration spectroscopy), and quality assurance/quality control are then systematically reviewed. Furthermore, the risks and impacts of MPs on soil properties, plants, animals, and antibiotic resistance genes (ARGs) between microorganisms and humans are discussed. At the end, this review also identifies the knowledge gaps and points out potential directions for future research. [ABSTRACT FROM AUTHOR]

In this paper, a series of color-tunable LiLaSiO 4 :βTm3+, γTb3+ phosphors were quickly synthesized by microwave-assisted solid-phase reaction method. Under proper ultraviolet light excitation, Tm3+ ions produce 1D 2 →3F 4 energy level transition and emit blue light, and the concentration quenching point is β = 1.5%mol. The color coordinates are (0.139, 0.046), compared with commercial blue phosphors. It has a higher color purity and color saturation. The Tb3+ ions produce 5D 4 →7F 5 energy level transition and emit green light, and the color coordinate is (0.324, 0.508). In Tm3+-Tb3+ double-doped LiLaSiO 4 phosphors, the concentration quenching point of Tb3+ ions is γ = 6%mol. By characterizing the fluorescence lifetime and the luminous intensity of the Tm3+-Tb3+ co-doped LiLaSiO 4 phosphor, it is verified that there is an energy transfer of Tm3+→Tb3+ in the phosphor. The energy transfer efficiency and energy transfer mechanism have been investigated in detail. From the researched luminous properties, it is found that Tm3+-Tb3+ co-doped LiLaSiO 4 phosphor is an ideal material for light-emitting diodes, luminescent materials and fluorescent display devices. • Novel LiLaSiO 4 :βTm3+,γTb3+ phosphors were prepared by microwave-assisted solid-phase reaction method. • LiLaSiO 4 :βTm3+,γTb3+ is a blue-green color tunable phosphor. • The energy transfer mechanism in LiLaSiO 4 :βTm3+,γTb3+ was demonstrated to be dipole-quadrupole interaction. • In LiLaSiO 4 :βTm3+,γTb3+ phosphors, the energy transfer efficiency is 82.78% and the quantum yield is 39.8%. • LiLaSiO 4 :βTm3+,γTb3+ phosphors have excellent temperature stability. [ABSTRACT FROM AUTHOR]

Several Li 2 Mg 1-x SiO 4 :xMn2+(x = 0.02, 0.04, 0.06, 0.08 and 0.10) phosphors were synthesized by a high temperature solid phase method and the quantum efficiency QE of these phosphors reaches 26.4%. Thus the Li 2 Mg 1-x SiO 4 :xMn2+ green phosphors have potential applications in the field of white LEDs activated by near-ultraviolet chips. [Display omitted] Several Li 2 Mg 1-x SiO 4 :xMn2+(x = 0.02, 0.04, 0.06, 0.08 and 0.10) phosphors were synthesized by a high temperature solid phase method. The structure, morphology, excitation and emission spectra, thermal stability, quantum efficiency, CIE color coordinates and fluorescence lifetime of these phosphors were studied by XRD, SEM, XPS and fluorescence spectrometry. The single pure Li 2 Mg 1-x SiO 4 :xMn2+ phosphors were obtained after 3 h of heating at 650 °C, followed by 3 h of heating at 1050 °C. When the monitoring wavelength is 537 nm, excitation peaks appear at 364, 384 and 446 nm. When the monitoring wavelength is 446 nm, an emission peak appears at 537 nm. The luminous color of the Li 2 Mg 1-x SiO 4 :xMn2+ phosphors corresponds to the green area on the CIE color coordinate. With an increase of the Mn2+ ion doping concentration, the emission intensity increases first and then decreases. The quenching point of the Mn2+ ion concentration is x = 0.06. This was found by testing the thermal stability of the Li 2 MgSiO 4 :0.06Mn2+ phosphor. With an increase in temperature, the emission intensity gradually decreases. The energy transfer mechanism is an electric dipole-electric dipole interaction. The fluorescence lifetime increases first and then decreases with the increase of the Mn2+ ion doping concentration. The quantum efficiency reaches 26.3%. Therefore, Li 2 Mg 1-x SiO 4 :xMn2+ green phosphors have potential applications in the field of white LEDs activated by near-ultraviolet chips. [ABSTRACT FROM AUTHOR]

Rapid and effective bone regeneration is still a major challenge in the clinical treatment of various bone diseases. Although recently developed electroactive materials have demonstrated high bone regeneration potential, the instability of the electrical stimulation and the unclear effects of the charge polarity on osteogenic differentiation hinder their clinical applications. In this work, GaN/AlGaN materials with well‐controlled polarity are used for the first time to induce endogenous electric stimulation and facilitate bone regeneration. By controlling the direction and magnitude of the piezoelectric and spontaneous polarization in the functional layer (GaN), charged GaN/AlGaN surfaces of opposite polarity, whose zeta potentials are within the range of the physiological potential, are obtained. Compared with N‐polarity GaN/AlGaN (with a positively charged surface), Ga‐polarity GaN/AlGaN (with a negatively charged surface) nanofilms show rapid and superior bone repair in vivo. In addition, the Ga‐polarity GaN/AlGaN hetero‐structures significantly promote the attachment, spreading, recruitment, and osteogenic differentiation of bone mesenchymal stem cells in vitro. Moreover, the bone morphogenetic protein‐6 (BMP6) expression profile in the early stages of osteogenic differentiation reveals that BMP6 may be an electrically sensitive osteogenic protein. This work sheds light on the application of III‐nitride materials in bone regeneration. [ABSTRACT FROM AUTHOR]

A novel photoelectrochemical (PEC) biosensor for the detection of DNA demethylase MBD2 was developed based on Bi 4 O 5 Br 2 –Au/CdS photosensitive material. Bi 4 O 5 Br 2 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 Bi 4 O 5 Br 2. 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. [Display omitted] • A PEC biosensor for detecting DNA demethylase MBD2 was constructed. • High sensitivity depended on the strong photoactivity of Bi4O5Br2–Au/CdS. • High specificity was originated from DNA demethylation triggered double-stranded DNA digestion. • The Inhibition of Cd2+ and perfluorohexanesulfonic acid on MBD2 activity were confirmed. [ABSTRACT FROM AUTHOR]

Abstract GaN-based light-emitting diodes (LEDs) on Si substrates are promising to replace conventional lamps due to the advantages of energy-saving and low-cost of LEDs grown on large-size Si substrates. However, high-density dislocations and cracks of GaN epitaxial films are usually formed that limit the further development and application of GaN-based LEDs. To circumvent the issues, the step-graded AlGaN buffer layers are carefully designed to grow GaN epitaxial films on Si substrates. The mechanisms of dislocations and stresses for GaN epitaxial films controlled by step-graded AlGaN buffer layers are also investigated by analyzing dislocations evolution and stresses relaxation at the hetero-interfaces. Afterwards, 3.0 μm-thick high-quality GaN epitaxial films grown on Si substrates have been obtained, and high-quality GaN-based LED wafers are obtained accordingly with small full-width at half-maximums (FWHMs) for GaN(0002) and GaN(10–12) X-ray rocking curves of 272 and 297 arcsec, respectively. The corresponding vertical-structure LED chips reveal high-performance with a high light output power of 592 mW and a small working voltage of 2.77 V @ 456 nm, at a current of 350 mA. This work provides an effective approach for the growth of high-quality crack-free GaN epitaxial films on Si substrates for the fabrication of high-performance GaN-based devices. Graphical abstract Image 1 Highlights • High-quality GaN epitaxial films have been grown on Si substrates by designing the step-graded AlGaN buffer layers. • The mechanisms of stress and dislocation density of GaN epitaxial films on 4-inch Si substrates have been revealed. • High-performance vertical-structure LEDs with high light output power of 592 mW @350 mA have been obtained. [ABSTRACT FROM AUTHOR]

High-quality AlN epitaxial films have been grown on Si substrates by optimizing the hydrofluoric acid (HF) solution for cleaning of Si substrates. Effect of the Si substrate surface on the surface morphology and structural property of AlN epitaxial films is investigated in detail. It is revealed that as the concentration of HF solution increases from 0 to 2.0%, the surface morphology and the crystalline quality are initially improved and then get worse, and show an optimized value at 1.5%. The as-grown ∼200 nm-thick AlN epitaxial films on Si substrates grown with HF solution of 1.5% reveal the root-mean-square (RMS) surface roughness of 0.49 nm and the full-width at half-maximum for AlN(0002) X-ray rocking curve of 0.35°, indicating the smooth surface morphology and the high crystalline quality. The corresponding mechanism is proposed to interpret the effect of Si substrate surface on surface morphology and structural property of AlN epitaxial films, and provides an effective approach for the perspective fabrication of AlN-based devices. [ABSTRACT FROM AUTHOR]

A high-quality AlN epitaxial film has been grown on a Si(111) substrate by metal–organic chemical vapor deposition through designing the AlN nucleation layer. The structure of a low temperature nucleation layer hinders the formation of amorphous SiNx in the AlN/Si heterointerface, reduces the dislocation density, and thereby improves the crystalline quality of the AlN epitaxial film. The influence of nucleation layer temperature on the surface morphology and the crystalline quality of the AlN epitaxial film is also revealed in detail. The AlN epitaxial film with the optimized nucleation layer grown at a temperature of 800 °C shows a sharp AlN/Si heterointerface, with an XRD full-width at half-maximum for AlN(0002) of 0.30°, and a very smooth surface with a root-mean-square surface roughness of 1.9 nm. Meanwhile, the 200 nm-thick AlN epitaxial film is almost fully relaxed with an in-plane tensile strain of only 0.42%. This work provides an effective approach for the growth of high-quality AlN epitaxial films in the application of AlN-based ultraviolet photonic devices and GaN-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Sorption is one of the most efficient and low cost strategies for volatile organic compound (VOC) removal, but VOC sorption by biochar has seen limited research. In this work, gas phase sorption experiments were conducted to determine the sorption potential and mechanisms of VOCs onto biochar. A total of 15 biochars produced from 5 common feedstocks at 300, 450, and 600 °C were evaluated as sorbents. Three common VOCs (acetone, cyclohexane, and toluene) were chosen as sorbates. The results showed that all the tested biochars had VOC sorption capacity in the range of 5.58–91.2 mg g −1 . The sorption capacities were mainly influenced by both the surface area of biochar and its noncarbonized organic matter content. The vapor sorption process was exothermic, and the removal of VOCs by the biochars decreased with increasing feedstock temperature. Both the physical adsorption and partition mechanisms played important roles in controlling the VOC removal by the biochars. Biochar maintained its VOC removal ability after five consecutive sorption-desorption cycles, which indicated good reusability. Findings of this work suggest that biochar is a promising alternative sorbent for gaseous VOC removal. [ABSTRACT FROM AUTHOR]

High-quality AlGaN epitaxial films have been grown on Si(1 1 1) substrates by metal-organic chemical vapor deposition through introducing an AlN layer followed by a high Al composition AlGaN buffer layer, together with optimizing the growth temperature to promote the dislocations reduction. The as-grown ∼400 nm-thick AlGaN epitaxial films with optimized growth temperature of 980 °C reveal high crystalline quality with a full-width at half-maximum for AlGaN(0 0 0 2) of 0.29° and smooth surface with a root-mean-square surface roughness of 0.76 nm. This work provides an effective approach for the growth of high-quality AlGaN epitaxial films in the application of ultraviolet lasers and detectors. [ABSTRACT FROM AUTHOR]

High-quality GaN epitaxial films have been grown on magnesium aluminate scandium oxide (ScMgAlO 4 ) substrates at low temperature of 450 °C with an in-plane epitaxial relationship of GaN[1-100]//ScMgAlO 4 [1-100]. It is found that the ~300 nm-thick GaN epitaxial films grown at 450 °C show the full-width at half-maximums (FWHMs) for GaN(0002) and GaN (10-12) of 0.18° and 0.40°, respectively, and very smooth surface with a root-mean-square (RMS) surface roughness of 1.5 nm. There is no interfacial layer existing between GaN and ScMgAlO 4 . However, as the growth temperature increases, the crystalline quality, surface morphology, and interfacial properties of as-grown GaN epitaxial films are deteriorated gradually. These GaN epitaxial films are of great importance for the fabrication of highly-efficient GaN-based devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • A PEC immunosensor for detecting RNA methylation was constructed. • The PEC biosensor based on g-C 3 N 4 /Bi 2 S 3 presented a higher photocurrent. • The detection limit was 0.025 nM for m6A RNA. • The effect of Pb2+-antibiotic on m6A RNA content of rice seedlings was detected. As an emerging analytical technology, photoelectrochemical (PEC) biosensor have attracted widespread attentions for detection of various targets. Herein, a simple, sensitive and selective PEC immunosensor was constructed for RNA methylation detection, where g-C 3 N 4 /Bi 2 S 3 with improved photoelectric properties was used as the photoactive material, anti-m6A antibody was employed as target recognition molecule, and the target of m6A RNA was also adopted as photocurrent inhibitor. Under optimal experimental conditions, the immunosensor presented wide linear range from 0.1 − 50 nM and low detection limit of 0.025 nM (S/N = 3). The immunosensor also possessed high stability. Considering the growing threat of heavy metal and antibiotic pollution to food security, the applicability of the develop method was assessed by investigating the effect of Pb2+-antibiotics binary pollutants on RNA methylation level in the leaves and roots of rice seedlings. [ABSTRACT FROM AUTHOR]

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. [Display omitted] • Fixed bed column packed with Al-modified biochar effectively removed SMX and SPY from wastewater. • SMX and SPY adsorption on Al-modified biochar was controlled by multiple mechanisms. • Yan model best described the breakthrough behaviors of SMX and SPY. • BDST model showed a strong linear relationship between service time and the amount of Al-modified biochar. [ABSTRACT FROM AUTHOR]

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. [Display omitted] • BiOBr/biochar composites were firstly synthesized by ball milling method. • Biochar increased the surface area and promoted charge transfer in composites. • There were strong interactions between BiOBr and biochar after ball milling. • Synergy between adsorption and photodegradation in BiOBr/biochar is elucidated. [ABSTRACT FROM AUTHOR]

[Display omitted] • The solvent-free ball-milling method obtains Z-scheme CeO 2 /g-C 3 N 4 heterojunction. • CeO 2 /g-C 3 N 4 thermodynamically has stronger redox potential and active radicals. • 70% CeO 2 /g-C 3 N 4 exhibited the best removal efficiency for MB photodegradation. • Synergy between adsorption and photodegradation of MB by CeO 2 /g-C 3 N 4 was identified. As a green solvent-free process, ball milling has attracted considerable attention in fabricating nanocomposites. Herein, we synthesized novel Z-scheme heterojunction CeO 2 /g-C 3 N 4 nanocomposites by simply direct ball milling CeO 2 and g-C 3 N 4 at three different mass ratios (3:7, 7:3, and 9:1). In comparison to individual CeO 2 and g-C 3 N 4 , the ball-milled nanocomposites showed stronger UV light response, higher charge carrier separation efficiency, greater photodegradation potential, higher photocurrent intensity, and faster electron transfer, indicating much better photocatalytic activity. When used as photocatalysts to remove methylene blue (MB) under UV light irradiation, 70% CeO 2 /g-C 3 N 4 exhibited the highest removal rate (90.1%), much better than that of CeO 2 (6.2%) or g-C 3 N 4 (45.7%). The synergistic interact between adsorption and photodegradation of the CeO 2 /g-C 3 N 4 nanocomposites was simulated by kinetic models, and a strong positive correlation (r = 0.834 and r s = 0.777) between adsorption and photocatalysis was identified. The results indicate that adsorption can promote photodegradation by accelerating the kinetics, while photodegradation can regenerate adsorption sites. This work provides not only a facile synthesis of Z-scheme heterojunction photocatalysts but also a novel perspective for better understanding the synergy between adsorption and photocatalysis. [ABSTRACT FROM AUTHOR]

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. [Display omitted] • ZnO/biochar nanocomposites were fabricated through simple ball milling. • Varied sized ZnO nanoparticles dispersed uniformly in the biochar matrix. • Ball milling increased the mesopores and macropores of nanocomposites. • Adsorption and photocatalytic activity were enhanced with proper ZnO addition. • BZ-X exhibited efficient MB removal by combining adsorption and photocatalysis. [ABSTRACT FROM AUTHOR]