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The poor processing and rheological properties of highly filled composites caused by the high loading of fillers can be improved with the use of maleic anhydride grafted polyethylene wax (PEWM) as compatibilizer and lubricant. In this study, two PEWMs with different molecular weights were synthesized by melt grafting, and their compositions and grafting degrees were characterized by Fourier transform infrared (FTIR) spectroscopy and acid-base titration. Subsequently, magnesium hydroxide (MH)/linear low-density polyethylene (LLDPE) composites with 60 wt% of MH were prepared using polyethylene wax (PEW) and PEWM, respectively. The equilibrium torque and melt flow index tests indicate that the processability and fluidity of MH/MAPP/LLDPE composites are significantly improved with the addition of PEWM. The addition of PEWM with a lower molecular weight leads to a substantial reduction in viscosity. The mechanical properties are also increased. The limiting oxygen index (LOI) test and cone calorimeter test (CCT) show that both PEW and PEWM have adverse effects on flame retardancy. This study provides a strategy to simultaneously improve the processability and mechanical properties of highly filled composites. [ABSTRACT FROM AUTHOR]

Atomic magnetometry has spectacular magnetic field sensitivity at room temperature. Here, we theoretically and experimentally investigate the benefits of a multi-pass cell in magnetometers using nonlinear magneto-optical rotation interrogation. Our theoretical analysis shows that there is an improvement in the signal-to-noise ratio (SNR) and consequently on the magnetic field sensitivity by carefully choosing the number of passes through the medium. In our specific case, we experimentally demonstrate a 160% enhancement in the magnetometer sensitivity by using a triple-pass cell, and it is consistent with our analysis on the SNR. This work provides a pathway to evaluate the benefits of multi-pass cells in high-performance atomic magnetometers. [ABSTRACT FROM AUTHOR]

β-Diketones are often used to separate brine with a high sodium-to‑lithium ratio but cannot be widely used because of their high toxicity and water solubility. In this work, a functionalized ionic liquid was synthesized from 4,4,4-trifluoro-1-phenyl-1,3-butanedione and 1-hexyl-3-methylimidazolium chloride, which was verified by FT-IR and 1H NMR spectroscopy. An organic phase system was formed with this ionic liquid as the extractant and 2-octanone as the diluent, which had the advantage of achieving good extraction and separation performances without co-extractant. In addition, the brine used in this work is the real Chaka salt lake brine in Tibet, which provides a reference value for industrial application of separation of metal ions. The experimental conditions were optimized and the single-stage extraction efficiency of Li+ reached up to 94 %. Using LiCl solution and HCl as the washing and stripping reagents, the washing efficiency of Na+ and stripping efficiency of Li+ were above 98 % and 99 %, respectively. The raffinate was used to regenerate the organic phase, which reduced the use of alkaline reagents. Over 10 cycles of the extraction process, the extraction efficiency of Li+ maintained at approximately 86 %. The extraction mechanism was identified as ionic association using slope analysis and ultraviolet and infrared measurements. • A novel extraction system was developed for selective extraction of lithium from Tibetan brine. • The single-stage extraction efficiency of Li+ with the extraction system reached up to 94 %. • The impurity ions could be washed out by using LiCl solutions. • The raffinate could be used to regenerate the organic phase. • The extraction system showed good reusability over 10 cycles of the extraction process. [ABSTRACT FROM AUTHOR]

Lithium is a vital aspect of the strategic development of the alternative energy and nuclear industries, and the demand for this metal is currently increasing rapidly. China possesses significant lithium resources, nearly 80 % of which are situated in salt lake brine. Solvent extraction is a viable means of extracting lithium ions from brine that has high magnesium-to-lithium ratio, and provides high selectivity along with ready scale-up to industrial production levels. The most common extraction technology for such scenarios is the tributyl phosphate (TBP)-FeCl 3 -kerosene system. However, this system tends to lose Fe3+ during the extraction process and the concurrent use of acid and alkali can seriously affect the stability of the organic phase. The present work demonstrates a new extraction process employing TBP as the main extractant, sodium tetraphenyl boron as a co-extractant and phenethyl isobutyrate as a diluent. Optimization of the relative amounts of these components along with the phase ratio provided a single-stage lithium ion extraction efficiency of 85.70 % together with a separation factor of lithium to magnesium ions of 1175. The organic phase was washed with a LiCl + NaCl solution to remove impurity ions then stripped five times with a NaHCO 3 solution, with a Li+ stripping efficiency >99 %. During ten replicate extractions, the Li+ extraction efficiency remained stable at approximately 84 %, demonstrating good stability. NMR spectra verified that the binding strength of metal cations to TBP decreased in the order of Li+ > Na+ ≫ Mg2+, indicating selectivity for the extraction of Li+. This single step NaHCO 3 method was adopted to simplify the extraction process. The overall strategy avoids the use of strong acids or bases that otherwise corrode equipment and provides greatly improved long-term stability of the organic phase. • TBP-sodium tetraphenyl boron-phenethyl isobutyrate extraction system was proposed. • A single-stage extraction efficiency of 85.70 % for lithium ion could be obtained. • The maximum separation factor of lithium to magnesium ions reached up to 1175. • NaHCO 3 was used as stripping agent to simplify the extraction process. • The proposed extraction system showed high stability and reusability. [ABSTRACT FROM AUTHOR]

For the atomic gyroscope (AG) operated in spin-exchange relaxation-free (SERF) regime, the sensitivity to external magnetic fields has been suppressed while the ability to sense inertial rotations has been kept. Here, a theoretical relationship between the magnetic fields and the AG response is given, and the influence of field fluctuations on the systematic stability is also shown. The spin-exchange rate of the electron spins R se en and the relaxation rate of the nuclear spins R tot n aggravate the influence of the field component B x . Experimental results indicate that the contributions of long-term fluctuations in the fields, approximately 2.4 pT/h for B x and 0.9 pT/h for B y , to the bias stability are 2.19 × 10 −2 deg/h and 5.29 × 10 −4 deg/h. This work is not only valuable for understanding the field-suppression effect in SERF AG, but also provides a useful tool for identifying the influence of fields on the systematic stability. [ABSTRACT FROM AUTHOR]

A few studies have reported transcanal endoscopic management of isolated congenital middle ear malformations (CMEMs). The purpose of this study is to describe our surgical experience in endoscopic ear surgery for isolated CMEMs and evaluate the surgical effect of hearing reconstruction. From January 2017 to January 2022, a retrospective study was performed on 36 patients (37 ears) with isolated CMEMs who all underwent endoscopic surgery. Demographic data, high-resolution computed tomography (HRCT) findings, intraoperative findings, surgical management and audiometric data were recorded. Anomalies were categorized according to the Teunissen and Cremers classification system: 8 ears were categorized as class I, 8 ears as class II, 19 ears as class III and 2 ears as class IV. The air conduction pure tone average (AC-PTA) of 37 cases was 61.5 ± 8.6 dB preoperatively and 29.6 ± 6.9 dB postoperatively (p < 0.001). The mean preoperative air-bone gap (ABG) significantly decreased from 43.1 ± 8.7 dB to 12.8 ± 5.5 dB postoperatively. 36 of 37 cases (97%) met the criteria for successful operation. Isolated CMEMs are mainly manifested as aplasia of the stapes' superstructure and dysplasia of the long process of the incus. Transcanal endoscopic surgery seems a safe technique for the management of isolated CMEMs. [ABSTRACT FROM AUTHOR]

• A novel ionic liquid of [Bmim]Bph 4 was used as co-extractant for extraction of Li+. • The single-stage Li/Mg separation factor was higher than 2500. • Li 2 CO 3 was obtained and the process flow was reduced with Na 2 CO 3 as stripping agent. • The binding capacity of TBP to metal ion followed the sequence Li+ ≫ Na+ > K+ ≈ Mg2+. • The whole extraction process with novel extraction system was green and efficient. A novel ionic liquid named 1-butyl-3-methylimidazolium tetraphenylboron ([Bmim]Bph 4) containing a stereo symmetric structure of Bph 4 - was synthesized and used as co-extractants with TBP and CH 2 BrCl as extractant and diluent for selective extraction of lithium ions from salt lake brines with high molar ratio of magnesium to lithium. The effects of extraction conditions containing molar ratio of co-extractant to lithium ion, volume percentage of TBP and O/A phase ratio on extraction performance were investigated. Under the optimal extraction conditions, the maximum separation factor of lithium to magnesium reached up to 2754 after one single-stage extraction process. After four stages of counter-current extraction process, the extraction efficiency of Li+ reached up to 99.47%. Then the washing and stripping conditions were optimized with the combination of LiCl and NaCl solution as the washing agent and Na 2 CO 3 solution as the stripping agent. After that, 10 cycles of the whole extraction experiments were carried out and the organic phase exhibited excellent reusability and stability. Since no acid and alkaline were used throughout the extraction process, the novel extraction process is greener and more environmentally friendly than the traditional solvent extraction process. [ABSTRACT FROM AUTHOR]

• ZnS QDs was synthesized using a facile method at room temperature. • The monodispersed ZnS QDs with narrow size distribution has been achieved. • ZnS QDs based photodetector with high performance has been fabricated. Zinc sulfide (ZnS) quantum dots (QDs) were synthesized using a facile, low-cost and environmentally friendly method at room temperature and ambient pressure. The structural, optical and electrical properties of the as-prepared ZnS QDs were investigated. The monodispersed crystalline ZnS QDs with an average size of 3.8 nm has been prepared, an absorption peak at 292 nm in the ultra-violet (UV) range was observed. The maximum responsivity (R) and detectivity (D *) of the ZnS QDs based photodetector under 365 nm UV light illumination were 5.8 A W−1 and 1.97 × 1013 Jones, respectively, which shows important potential application in UV detection. [ABSTRACT FROM AUTHOR]

• A new TBP-FeCl 3 -P204-kerosene system was used for selective extraction of lithium. • The single-stage extraction efficiency of Li+ was 52.71% under optimal conditions. • The proposed extraction process did not use additional acid-base solutions. • Pure water could be used as washing and stripping agents. • Fe(III) was loaded in the organic phase with FeCl 4 - and Fe3+ bonding to TBP and P204. The tributyl phosphate (TBP)–FeCl 3 –kerosene system is a common tool for lithium extraction from salt lakes. This system has two main problems. One, FeCl 4 − is unstable, which decreases the lithium extraction efficiency. Two, TBP readily degrades after long-term contact with high concentrations of acids and bases. Accordingly, the present authors introduce di(2-ethylhexyl) phosphate (P204) in conjunction with Fe3+ to construct a TBP–FeCl 3 –P204–kerosene extraction system. The optimal operating conditions were 10% P204 + 40% TBP + kerosene, an Fe3+/Li+ molar ratio of 1.6, and organic-to-acid phase ratio R(O/A) = 1. The final lithium ion single-stage extraction yield was 52.71%. The former washed 90.64% of Mg2+ when R(O/A) = 70, the latter washed 95.37% of Mg2+ when R(O/A) = 20. Using water as the stripping agent, the Li+ stripping efficiency decreased with increasing R(O/A). Ultraviolet and Raman spectroscopy indicated that TBP underwent complexation with Li+ and FeCl 4 −, whereas P204 underwent complexation with Fe3+ only. When the Cl− concentration was low, Fe3+ underwent complexation with P204 and was retained in the organic phase; whereas when the Cl− concentration was high, FeCl 4 − formed again in a manner that facilitated co-extraction with Li+ by TBP. [ABSTRACT FROM AUTHOR]

Solar-to-hydrogen energy conversion is a promising strategy to solve environmental pollution and energy crisis by utilizing photocatalytic water splitting. In this work, a "sandwich" structure of g-C3N4-based single-atom platinum (Pt) catalyst for photocatalytic water splitting is proposed and investigated using a combined first principles and semi-empirical study method. The calculation results indicate that, without any co-catalyst, the photogenerated holes in the valence band of BL-g-C3N4 cannot oxidize H2O to O2, and its oxygen evolution reaction (OER) performance is not better than that of the pristine monolayer g-C3N4. Significantly, the photogenerated holes in the valence band of the "sandwich"-structured photocatalyst g-C3N4–Pt1–g-C3N4 can oxidize H2O to O2 without any co-catalyst. That is, the OER performance of g-C3N4–Pt1–g-C3N4 is better than that of the pristine g-C3N4 and the pristine bilayer-g-C3N4 (BL-g-C3N4). However, it can be found that the introduction of single Pt atom confinement in the BL-g-C3N4 cannot effectively reduce hydrogen evolution reaction (HER) energy barrier or improve the hydrogen evolution kinetics of BL-g-C3N4. In other words, the introduction of the confined single Pt atom in the BL-g-C3N4 not only fails to improve HER performance of BL-g-C3N4, but deteriorates HER catalytic performance of BL-g-C3N4. These findings provide some theoretical insights for engineers to prepare photocatalysts with higher activity and stability. [ABSTRACT FROM AUTHOR]

Maleic anhydride-modified homopolymerized polypropylene (PP-g-MAH) and maleic anhydride-modified polyolefin elastomer (POE-g-MAH) were used as bulking agents to improve the poor processing and mechanical properties of highly filled composites due to high filler content. In this study, a series of linear low-density polyethylene (LLDPE)/magnesium hydroxide (MH) composites were prepared by the melt blending method, and the effects of the compatibilizer on the mechanical properties, flame retardancy, and rheological behavior of the composites were investigated. The addition of the compatibilizer decreased the limiting oxygen index (LOI) values of the composites, but they were all greater than 30.00%, which belonged to the flame retardant grade. Mechanical property tests showed that the addition of the compatibilizer significantly increased the tensile and impact strengths of the LLDPE/60MH (MH addition of 60 wt%) composites. Specifically, the addition of 5 wt% POE-g-MAH increased 154.07% and 415.47% compared to the LLDPE/60MH composites, respectively. The rotational rheology test showed that the addition of the compatibilizer could effectively improve the processing flow properties of the composites. However, due to the hydrocarbon structure of the compatibilizer, its flame retardant properties were adversely affected. This study provides a strategy that can improve the processing and mechanical properties of highly filled composites. [ABSTRACT FROM AUTHOR]

Forest conversion is a common management practice in forestry, yet the effects of forest conversion on the transformation of phosphorus (P) fractions remain unclear. This work aims at assessing the changes in soil P fractions, including total P (TP), available P (AP), inorganic P (Pi), organic P (Po) and microbial biomass P (MBP) after natural conversion of Chinese fir plantations (CFP) to evergreen broad-leaved forests (EBLF) in subtropical China. Results showed the contents of soil TP and Po were not affected by the forest conversion, but soil AP and MBP concentrations and their proportion significantly increased with forest conversion from CFP to EBLF. The contents of soil P fractions were significantly accumulated in the topsoil (0–20 cm) in the studied forests. Additionally, soil P contents were higher in the winter–spring seasons than in the summer–fall seasons during the period of study. Soil AP content was positively correlated with TP, Po, Pi, labile organophosphorus (LOP), moderate labile organophosphorus (MLOP), moderate resistant organophosphorus (MROP), aluminum–bound P (Al–P), iron–bound P (Fe–P) and MBP contents in EBLF, while the content of soil AP was positively related to Po, LOP, MLOP, Al–P, Fe–P and MBP contents in CFP. Path analysis showed that the most important factor in affecting soil P availability was Po (LOP and HROP) in EBLF stands and was Al–P in CFP stands. Our study suggested that management practices in conserving soil Pi (especially in Al–P) in the CFP and in increasing Po inputs in the EBLF would improve soil P availability in subtropical forests. [ABSTRACT FROM AUTHOR]

Feasibility assessment of endoscopic ear surgery (EES) relies solely on subjective evaluation by surgeons. Extracting radiomic features from preoperative CT images of the external auditory canal, we aim to classify EES patients into easy and difficult groups and improve accuracy in determining surgery feasibility. 85 patients' external auditory canal CT scans were collected and 139 radiomic features were extracted using PyRadiomics. The most relevant features were selected and three machine learning algorithms (logistic regression, support vector machine, and random forest) were compared using K-fold cross-validation (k = 5) to predict surgical feasibility. The best-performing machine learning model, the support vector machine (SVM), was selected to predict the difficulty of EES. The proposed model achieved a high accuracy of 86.5%, and F1 score of 84.6%. The area under the ROC curve was 0.93, indicating good discriminatory power. The proposed machine learning model provides a reliable and accurate method for classifying patients undergoing otologic surgery based on preoperative imaging data. The model can help clinicians to better prepare for challenging surgical cases and optimize treatment plans for individual patients. [ABSTRACT FROM AUTHOR]

The novel heteropolyacid ionic liquid 1-methylimidazolium silicotungstate ([Mmim] 4 SiW 12 O 40) was synthesized using a one-step method and subsequently characterized. This compound was then employed as a co-extractant for the removal of lithium from salt lake brine having a high Mg/Li molar ratio, in conjunction with tributyl phosphate (TBP) and γ-heptanolide as the extractant and diluent, respectively. The optimal extraction conditions gave a single-stage lithium ion extraction efficiency of approximately 60 %. More environmentally friendly and efficient processes were also developed. In one approach, a portion of the aqueous phase containing only HCl and LiCl after stripping was used for washing along with an aqueous HCl solution as the stripping agent and Mg(OH) 2 for regeneration. In the alternative method, NaCl and LiCl were used as washing agents while Na 2 CO 3 was employed for stripping and regeneration, reducing the time required without the need for strong acids or bases. This system showed good extraction efficiency stability over 10 consecutive cycles. The mechanism of this process was explored using Fourier transform infrared spectroscopy and 31P nuclear magnetic resonance spectroscopy and the binding capacity of TBP for the metals was found to decrease in the order of Li+ > Na+ > Mg2+ > K+. • The proposed heteropolyacid ionic liquid was synthesized by one-step method. • The single-stage extraction efficiency of lithium ion was approximately 60 %. • The proposed extraction system showed high selectivities for Mg2+, Na+ and K+. • Na 2 CO 3 was used as stripping agent for shorting the process flow. • The proposed extraction system showed good reusability and stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • NaBPh 4 and CH 2 ClBr were used as co-extractant and diluent for extraction of Li+. • The new extraction system showed excellent extraction performance and reusability. • Using Na 2 CO 3 as stripping agent obtained Li 2 CO 3 product and reduced the process flow. • The binding capacity of TBP to metal ion followed the sequence Li+ > Na+ > K+ > Mg2+. • None of acid and alkali were used in the whole extraction process. It is very difficult to selectively extract lithium ions from high Mg/Li salt lake brine efficiently and environmentally. Among the conventional extraction system, FeCl 3 as the co-extractant has the disadvantages of easy to loss and reducing stability of the organic phase. Therefore, a new co-extractant must be developed and applied for selective extraction of lithium ions. TBP was used as the extractant. According to the optimization of extraction conditions, NaBPh 4 and CH 2 ClBr were selected as the suitable co-extractant and diluent. Under the optimal extraction conditions (molar ratio of NaBPh 4 to Li+ = 2.0, TBP volume fraction = 50%, and R (O/A) = 1.0), the one-stage extraction efficiency of Li+ and Li/Mg separation factor reached up to 87.65% and 2260.71, respectively. Effects of washing and stripping conditions on washing and stripping performances were investigated too. Under optimal conditions of washing and stripping processes, the stripping efficiency of Li+ reached up to 98.84% and Li 2 CO 3 product could be directly obtained in the aqueous phase. Then ten continuous cycles of the whole extraction processes were performed and the results verified that the extraction system showed excellent extraction stability and reusability. The extraction mechanism was deeply studied by using simulation calculation on Materials Studio software and nuclear magnetic resonance characterization. The binding capacity of TBP to metal ions follows the sequence: Li+ > Na+ > K+ > Mg2+. This proposed extraction technology not only avoids the use of acid and alkali, but also reduces the process flow, which has great research potential and industrialization value. [ABSTRACT FROM AUTHOR]

As human population growth and waste from technologically advanced industries threaten to destabilise our delicate ecological equilibrium, the global spotlight intensifies on environmental contamination and climate-related changes. These challenges extend beyond our external environment and have significant effects on our internal ecosystems. The inner ear, which is responsible for balance and auditory perception, is a prime example. When these sensory mechanisms are impaired, disorders such as deafness can develop. Traditional treatment methods, including systemic antibiotics, are frequently ineffective due to inadequate inner ear penetration. Conventional techniques for administering substances to the inner ear fail to obtain adequate concentrations as well. In this context, cochlear implants laden with nanocatalysts emerge as a promising strategy for the targeted treatment of inner ear infections. Coated with biocompatible nanoparticles containing specific nanocatalysts, these implants can degrade or neutralise contaminants linked to inner ear infections. This method enables the controlled release of nanocatalysts directly at the infection site, thereby maximising therapeutic efficacy and minimising adverse effects. In vivo and in vitro studies have demonstrated that these implants are effective at eliminating infections, reducing inflammation, and fostering tissue regeneration in the ear. This study investigates the application of hidden Markov models (HMMs) to nanocatalyst-loaded cochlear implants. The HMM is trained on surgical phases in order to accurately identify the various phases associated with implant utilisation. This facilitates the precision placement of surgical instruments within the ear, with a location accuracy between 91% and 95% and a standard deviation between 1% and 5% for both sites. In conclusion, nanocatalysts serve as potent medicinal instruments, bridging cochlear implant therapies and advanced modelling utilising hidden Markov models for the effective treatment of inner ear infections. Cochlear implants loaded with nanocatalysts offer a promising method to combat inner ear infections and enhance patient outcomes by addressing the limitations of conventional treatments. • Nanocatalyst-loaded cochlear implants offer targeted treatment for inner ear infections. • Enhanced therapeutic outcomes with controlled release of nanocatalysts. • Effectiveness demonstrated in eliminating infections and promoting tissue regeneration. • Hidden Markov Models aid precise instrument location during surgery. • Bridging cochlear implant therapies and advanced modelling for effective treatment. [ABSTRACT FROM AUTHOR]

• Beside the main phase of zincblende, a small amount of wurtzite is existed in CVD ZnS. • The mechanical properties of CVD ZnS were characterized with a slight variation of Zn/S ratio. • Zn 46.84 S 53.16 presents a high flexural strength of 133.8 MPa. • XRD, SEM, and Raman spectra of CVD ZnS were conducted. Polycrystalline ZnS samples with a slight composition fluctuation are grown by chemical vapor deposition (CVD) method, and their optical and mechanical properties and microstructure were investigated in detail. The CVD samples present a maximum transmittance of ∼73% in the 7–10 μm region. By changing the sulfur content, a maximum Knoop hardness of 2.375 GPa was found in the Zn 50.06 S 49.94 sample, while Zn 46.84 S 53.16 presents a high flexural strength of 133.8 MPa. The microstructural origin of this abnormal changing of mechanical properties was discussed according to the results of micrographs, XRD patterns and Raman spectra. The results suggest that beside the main phase of zincblende, a small amount of wurtzite is existed. This composited microstructure is responsible for the higher hardness and strength of CVD ZnS. [ABSTRACT FROM AUTHOR]

We describe a dual-axis atomic spin gyroscope based on an alkali metal-noble gas comagnetometer. Alkali metal vapor is optically pumped, and then the noble gas is hyperpolarized along the z axis. When sensing a transverse rotation, the polarized noble gas will be induced to precess and produce an effective magnetic field in the x – y plane for alkali metals to precess under. Operating in the spin-exchange relaxation-free regime, alkali atoms are modulated by the z axis magnetic field and serve as an integrated in-situ dual-axis magnetometer to detect the gyroscopic precession in the x and y axes simultaneously, using a single probe beam. By using the parametric modulation technique, the low frequency drift is effectively suppressed and a bias instability of less than 0.05 deg/h has been achieved in our dual-axis atomic spin gyroscope. [ABSTRACT FROM AUTHOR]

Atomic spin gyroscope (ASG) based on comagnetometer is a high sensitive and compact gyroscope for future inertial navigation applications. The start-up time was several hours of the demonstrated ASGs based on He-K or Ne-Rb-K comagnetometer, and only a few inertial navigation applications allow such a long time for preparation. We report the demonstration of an ASG based on Xe-Cs comagnetometer, which decreases the start-up time to 10 minutes and decreases the operation temperature by 40% as well. By operating this ASG in spin exchange relaxation free regime, a sensitivity of 7×10 °/(s Hz) was achieved. [ABSTRACT FROM AUTHOR]