Maximizing resource recovery: A green and economic strategy for lithium extraction from spent ternary batteries.

Spent ternary lithium-ion batteries contain abundant lithium resource, and their proper disposal is conducive to environmental protection and the comprehensive utilization of resources. Separating valuable metals in the ternary leaching solution is the key to ensuring resource recovery. However, the traditional post-lithium extraction strategies, which heavily rely on ion exchange to remove transition metal ions in the leachate, encounter challenges in achieving satisfactory lithium yields and purities. Based on this, this paper proposed a new strategy to prioritize lithium extraction from ternary leachate using "(+) LiFePO4/FePO4 (-)" lithium extraction system. The preferential recovery of lithium can be realized by controlling the potential over 0.1 V versus Standard Hydrogen Electrode (SHE) without introducing any impurity ions. The lithium recovery rate reaches 98.91%, while the rejection rate of transition ions exceeds 99%, and the separation coefficients of lithium to transition metal ions can reach 126. Notably, the resulting lithium-rich liquid can directly prepare lithium carbonate with a purity of 99.36%. It provides a green and efficient strategy for the preferential recovery of lithium from the spent ternary leachate.

The prognostic values of estimating intraperitoneal pressure in the occurrence of abdominal wall complications in peritoneal dialysis patients.

BACKGROUND: Increased intraperitoneal pressure is associated with abdominal wall complications and technical failure of peritoneal dialysis (PD). Several equations have been developed to estimate intraperitoneal pressure. We aimed to assess the prognostic yield of the intraperitoneal pressure as estimated by current equations on the occurrence of abdominal wall complications in peritoneal dialysis patients. METHODS: This is a retrospective analysis of data from a prospective cohort which recruited 1207 incident PD patients. Estimated intraperitoneal pressure was calculated using four available equations (according to Sigogne, Castellanos, Scanziani and de Jesus Ventura). Abdominal wall complications were recorded during follow-up. Univariate analysis and multivariate analysis with competing risk regression were used to assess the predictive power of the estimates of intraperitoneal pressure in the occurrence of abdominal wall complications. RESULTS: During a median follow-up of 30 months, 66 (5.5%) patients (1.6/100 patient-years) developed abdominal wall complications. The median time to the occurrence of abdominal wall complications was 5.7 months. Only the estimated intraperitoneal pressure by the de Jesus Ventura equation significantly predicted abdominal wall complications by using univariate analyses. Associations between estimated intraperitoneal pressure by the de Jesus Ventura equation and the occurrence of abdominal wall complications disappeared after adjusting for significant clinical factors. CONCLUSIONS: We verified the prognostic value of estimation of intraperitoneal pressure by four available equations in predicting abdominal wall complications in our single-center PD cohort. Due to a low diagnostic yield, a novel equation for estimating the intraperitoneal pressure is urgently needed.

Regulation Mechanisms and Maintenance Strategies of Stemness in Mesenchymal Stem Cells.

Stemness pertains to the intrinsic ability of mesenchymal stem cells (MSCs) to undergo self-renewal and differentiate into multiple lineages, while simultaneously impeding their differentiation and preserving crucial differentiating genes in a state of quiescence and equilibrium. Owing to their favorable attributes, including uncomplicated isolation protocols, ethical compliance, and ease of procurement, MSCs have become a focal point of inquiry in the domains of regenerative medicine and tissue engineering. As age increases or ex vivo cultivation is prolonged, the functionality of MSCs decreases and their stemness gradually diminishes, thereby limiting their potential therapeutic applications. Despite the existence of several uncertainties surrounding the comprehension of MSC stemness, considerable advancements have been achieved in the clarification of the potential mechanisms that lead to stemness loss, as well as the associated strategies for stemness maintenance. This comprehensive review provides a systematic overview of the factors influencing the preservation of MSC stemness, the molecular mechanisms governing it, the strategies for its maintenance, and the therapeutic potential associated with stemness. Finally, we underscore the obstacles and prospective avenues in present investigations, providing innovative perspectives and opportunities for the preservation and therapeutic utilization of MSC stemness.

Biomechanical stability of oblique lateral interbody fusion combined with four types of internal fixations: finite element analysis.

Objective: Using finite element analysis to identify the optimal internal fixation method for oblique lateral lumbar interbody fusion (OLIF), providing guidance for clinical practice. Methods: A finite element model of the L4 - L5 segment was created. Five types of internal fixations were simulated in the generated L4-L5 finite element (FE) model. Then, six loading scenarios, i.e., flexion, extension, left-leaning, right-leaning, rotate left, and rotate right, were simulated in the FE models with different types of fixations. The biomechanical stability of the spinal segment after different fixations was investigated. Results: Regarding the range of motion (ROM) of the fused segment, OLIF + Bilateral Pedicle Screws (BPS) has a maximum ROM of 1.82° during backward bending and the smallest ROM in all directions of motion compared with other models. In terms of the von Mises stress distribution on the cage, the average stress on every motion direction of OLIF + BPS is about 17.08MPa, and of OLIF + Unilateral Vertebral Screw - Pedicle Screw (UVS-PS) is about 19.29 MPa. As for the von Mises stress distribution on the internal fixation, OLIF + BPS has the maximum internal fixator stress in left rotation (31.85 MPa) and OLIF + Unilateral Pedicle Screw (UPS) has the maximum internal fixator stress in posterior extension (76.59 MPa). The data of these two models were smaller than those of other models. Conclusion: OLIF + BPS provides the greatest biomechanical stability, OLIF + UPS has adequate biomechanical stability, OLIF + UVS-PS is inferior to OLIF + UPS synthetically, and OLIF + Double row vertical screw (DRVS) and Individual OLIF (IO) do not present significant obvious advantages.

Lab-on-fiber: laser-induced micro-cavity for a relative humidity measurement.

The lab-on-fiber design philosophy is the foundation for creating high-performance integrated fiber sensors. Hence, this Letter proposes an ultra-compact Fabry-Perot interferometer (FPI) based on a laser-induced micro-cavity (LIMC-FPI) on a fiber end for measuring relative humidity. To our knowledge, this novel approach, named the fiber-end photopolymerization (FEP) technique, is applied to create a micro-cavity. Specifically, a pair of humidity-sensitive polymer pillars and a resin end cap obtained by FEP are integrated to generate the cavity. As the ambient humidity changes, the pillars lengthen or shorten, resulting in the spectral evolution of the LIMC-FPI. A typical humidity sensitivity of 0.18 nm/%RH is obtained experimentally. For monitoring the human breathing process, the LIMC-FPI is responsive in the breathing frequency range of 0.2 to 0.5 Hz, allowing a response and recovery time of less than 0.388 s and 1.171 s, respectively. This work introduces a fresh and cost-effective approach for developing lab-on-fiber concept-based sensors.

EEG and ECG-Based Multi-Sensor Fusion Computing for Real-Time Fatigue Driving Recognition Based on Feedback Mechanism.

A variety of technologies that could enhance driving safety are being actively explored, with the aim of reducing traffic accidents by accurately recognizing the driver's state. In this field, three mainstream detection methods have been widely applied, namely visual monitoring, physiological indicator monitoring and vehicle behavior analysis. In order to achieve more accurate driver state recognition, we adopted a multi-sensor fusion approach. We monitored driver physiological signals, electroencephalogram (EEG) signals and electrocardiogram (ECG) signals to determine fatigue state, while an in-vehicle camera observed driver behavior and provided more information for driver state assessment. In addition, an outside camera was used to monitor vehicle position to determine whether there were any driving deviations due to distraction or fatigue. After a series of experimental validations, our research results showed that our multi-sensor approach exhibited good performance for driver state recognition. This study could provide a solid foundation and development direction for future in-depth driver state recognition research, which is expected to further improve road safety.

ECG Multi-Emotion Recognition Based on Heart Rate Variability Signal Features Mining.

Heart rate variability (HRV) serves as a significant physiological measure that mirrors the regulatory capacity of the cardiac autonomic nervous system. It not only indicates the extent of the autonomic nervous system's influence on heart function but also unveils the connection between emotions and psychological disorders. Currently, in the field of emotion recognition using HRV, most methods focus on feature extraction through the comprehensive analysis of signal characteristics; however, these methods lack in-depth analysis of the local features in the HRV signal and cannot fully utilize the information of the HRV signal. Therefore, we propose the HRV Emotion Recognition (HER) method, utilizing the amplitude level quantization (ALQ) technique for feature extraction. First, we employ the emotion quantification analysis (EQA) technique to impartially assess the semantic resemblance of emotions within the domain of emotional arousal. Then, we use the ALQ method to extract rich local information features by analyzing the local information in each frequency range of the HRV signal. Finally, the extracted features are classified using a logistic regression (LR) classification algorithm, which can achieve efficient and accurate emotion recognition. According to the experiment findings, the approach surpasses existing techniques in emotion recognition accuracy, achieving an average accuracy rate of 84.3%. Therefore, the HER method proposed in this paper can effectively utilize the local features in HRV signals to achieve efficient and accurate emotion recognition. This will provide strong support for emotion research in psychology, medicine, and other fields.

Novel equations for estimating intraperitoneal pressure among peritoneal dialysis patients.

Background: Increased intraperitoneal pressure (IPP) is associated with abdominal wall complications and technical failure in peritoneal dialysis (PD). Since the standard measurement of IPP is limited due to its cumbersome procedures, we aimed to develop and validate equations for estimating IPP. Methods: We performed a cross-sectional study with a total of 200 prevalent PD patients who were divided into development and validation datasets after random sampling matched by body mass index. The IPPs were measured using the Durand method, with whole-body and abdominal anthropometry indices collected. Equations with 2.0-L and 1.5-L fill volumes were generated by stepwise linear regression modelling. The bias, accuracy and precision of the estimated IPP (eIPP) with 2-L and 1.5-L fill volumes were compared with actual IPPs by the Durand method. The eIPP for the 2-L fill volume was also compared with other existing equations. Results: Two new equations incorporating waist circumference and height from the decubitus plane to mid-axillary line were generated. The eIPPs exhibited small biases in relation to the Durand method , with median differences of -0.24 cmH2O and -0.10 cmH2O for 2 L and 1.5 L, respectively. The precisions evaluated by the standard deviation of the absolute value of the differences were 2.59 cmH2O and 2.50 cmH2O, respectively. The accuracies evaluated by the value of the percentage of estimates that differed by >20% for the eIPP were 26% for 2.0 L and 27% for 1.5 L. Better bias, precision and accuracy were observed for the eIPP equation compared with other existing equations for the 2.0-L fill volume. Conclusions: We provided two new equations developed from abdominal anthropometry indices to accurately estimate the IPP in the PD population.

Exoskeleton type long-period fiber grating for cross-talk-resistance single-parameter measurement.

This paper proposes a new, to the best of our knowledge, design framework of long-period fiber grating (LPFG) sensors resistant to multi-parameter cross talk. A section of hollow quartz capillary (HQC), which acts as an exoskeleton, is periodically merged with a single-mode fiber (SMF) by the arc-discharge method. The mechanical stress in the SMF is released while the thermal stress is enhanced after a high-temperature fusion process. Under the influence of the elastic-optical effect, the refractive index of the core is periodically modulated along the axial direction to form an exoskeleton long-period fiber grating (Es-LPFG). The unique exoskeleton structure not only induces mode coupling but also enables the proposed device to resist cross talk among the strain, ambient refractive index, and vector bending. The temperature is able to be measured independently with a sensitivity of 74 pm/ ∘C. The novel Es-LPFG is promising in single-parameter sensing, mode-locked lasers, and frequency-locked gain flattening.

Tuning the coordination environment of Fe atoms enables 3D porous Fe/N-doped carbons as bifunctional electrocatalyst for rechargeable zinc-air battery.

As one of the most promising candidates for power sources, the rechargeable Zn-air batteries have attracted much attention due to their high energy density. However, Zn-air batteries suffer from sluggish kinetics of oxygen reduction (ORR) and oxygen evolution reaction (OER) during the discharge and charge process. Herein, a FeN2-doped carbon with a unique three-dimensional (3D) porous structure (CeO2-FeNC-5) was synthesized as an electrocatalyst for Zn-air batteries by one-step pyrolysis and introducing CeO2 to tune the coordination environment of Fe atoms. Extended X-ray absorption fine structure (EXAFS) results indicate that the introduction of CeO2 can convert FeN3 moieties into FeN2 moieties. The CeO2-FeNC-5 exhibits a more positive half-wave potential of 0.902 V for ORR, and a low overpotential of 0.327 V at 10 mA cm-2 for OER. Furthermore, the Zn-air battery with CeO2-FeNC-5 achieve a maximum power density (169 mW cm-2), a high open voltage platform (1.47 V) and superior cycling stability (200 h). The unique 3D porous structure provides channels for mass transport and exposes sufficient active sites to facilitate the ORR and OER processes. Calculations prove that FeN2 moieties are beneficial to O2 adsorption on Fe/N-doped carbon surface. This work provides an effective strategy for designing and synthesizing FeNx-doped carbon matrix electrocatalysts for sustainable metal-air batteries.

Dual Inorganic Sacrificial Template Synthesis of Hierarchically Porous Carbon with Specific N Sites for Efficient Oxygen Reduction.

It is still a challenge to achieve efficiently controlled preparation of functional oxygen reduction reaction (ORR) carbon electrocatalysts with multi-preferred structures (hierarchically porous networks and specific carbon-nitrogen bonds) from carbohydrate-containing small molecules via simple one-step pyrolysis. Based on the step-by-step spontaneous gas-foaming strategy, we successfully prepare 3D hierarchically porous networks with tunable N sites (NP/NG ≈ 1:1) by pyrolyzing diverse carbohydrates (glucose, maltose, and cyclodextrin) using nonmetal-metal dual inorganic sacrificial templates. In situ evaporation templates can simplify the procedure of the experiments and avoid the active site loss compared with traditional hard templates. Crucially, dual inorganic sacrificial templates can induce abundant defects and microscopic pore structures (the specific surface area increased from 922.403 to 1898.792 m2·g-1) and tunable N sites compared with single nonmetal sacrificial templates. The regulatory mechanism of dual inorganic templates on N sites (NP/NG ≈ 1:1) is independent of the polymeric state of carbohydrate precursors or even the carbonization condition of the pyrolysis process. A series of carbon materials prepared by this strategy all have ORR-preferred structures and exhibit low ORR overpotentials compared with Pt/C. For instance, the Zn-air battery with ßCD-DSC-950-1 exhibits an open-circuit potential of 1.51 V and a peak power density of 180.89 mW·cm-2, higher than those of Pt/C (1.47 V, 174.94 mW·cm-2). In general, the conversion of carbohydrate-containing small molecules to functional carbon materials provides a new strategy for the development of carbonaceous electrocatalysts.

Chirality Induces the Self-Assembly To Generate a 3D Porous Spiral-like Polyhedron as Metal-Free Electrocatalysts for the Oxygen Reduction Reaction.

The sluggish kinetics and large overpotential of the oxygen reduction reaction (ORR) severely limit the widespread production and application of metal-air batteries. Herein, a conductive three-dimensional (3D) porous spiral-like polyhedron structure composed of nitrogen-doped carbon nanosheets (L/D-SPNC) was utilized as catalysts with combination of 3D hierarchical porous properties and distinguishing intrinsic properties of two-dimensional (2D) nanosheets for ORR. The chiral template, l/d-tartaric acid, induces the self-assembly of the supramolecule and the formation of an orderly array of carbon with spiral-like surface feature on a molecular scale. The resulting L/D-SPNC exhibits a small wall thickness (2.5 nm), large specific surface area (2034.2 m2/g), and high conductivity (155.76 S/m), which indicates that the properties of 2D nanosheets building blocks are kept in 3D mode. As catalysts for ORR, the optimized L-SPNC-950-1 exhibits a more positive onset potential of 1.03 V compared with those of Pt/C (1.00 V) and a half-wave potential of 0.87 V is also comparable to those of Pt/C (0.87 V). Al-air battery discharge data demonstrate that the spiral-like structure facilitates the diffusion of the electrolyte and oxygen on a three-phase interface, causing weak polarization. Density functional theory (DFT) calculations prove that the twisted surface aggravates the differential charge distribution between C-C/C-N bonds.

Rotamers of p­isopropylphenol studied by hole-burning resonantly enhanced multiphoton ionization and mass analyzed threshold ionization spectroscopy.

The resonance enhanced multiphoton ionization (REMPI), ultraviolet-ultraviolet (UV-UV) hole burning and mass analyzed threshold ionization (MATI) spectroscopy have been applied to investigate the vibrational features of p­isopropylphenol in its first electronically excited state S1 and cationic ground state D0. Two stable conformational structures of p­isopropylphenol are distinctly found in the supersonic molecular beam and identified as the cis and trans rotamers through REMPI and UV-UV hole burning spectroscopy. The electronic excitation energies of S1 ← S0 transition of two rotamers are determined to be 35,578 and 35,593 cm-1, and the adiabatic ionization energies are 65,331 and 65,350 cm-1, respectively. The MATI spectra recorded via different intermediate levels of S1 state indicate the similarity in the molecular geometry between the S1 state and the D0 state for each rotamer of p­isopropylphenol. Geometrical optimizations of p­isopropylphenol have also been performed using the density functional theory (DFT) for S0 and D0 states, and time-dependent density functional theory (TDDFT) for S1 state. The simulated spectra for S1 ← S0 and D0 ← S1 transitions of two rotamers are able to reproduce qualitatively the experimental spectral profile, which help us to assign the vibronic modes. Most of the observed vibrations of two rotamers in the S1 and D0 states are related to the in-plane ring deformation and some active modes involving isopropyl group.

Metal-Organic Framework-Derived Reduced Graphene Oxide-Supported ZnO/ZnCo2O4/C Hollow Nanocages as Cathode Catalysts for Aluminum-O2 Batteries.

Aluminum-air battery is a promising candidate for large-scale energy applications because of its low cost and high energy density. Remarkably, tremendous efforts have been concentrated on developing efficient and stable cathode electrocatalysts toward the oxygen reduction reaction. In this work, a hydrothermal-calcination approach was utilized to prepare novel reduced graphene oxide (rGO)-supported hollow ZnO/ZnCo2O4 nanoparticle-embedded carbon nanocages (ZnO/ZnCo2O4/C@rGO) using a zeolitic imidazolate framework (ZIF-67)/graphene oxide/zinc nitrate composite as the precursor. The ZnO/ZnCo2O4/C@rGO hybrid exhibits remarkable electrocatalytic performance for oxygen reduction reaction under alkaline conditions and superior stability and methanol tolerance to those of the commercial Pt/C catalyst. Furthermore, novel and simple Al-air coin cells were first fabricated using the hybrid materials as cathode catalysts under ambient air conditions to further investigate their catalytic performance. The coin cell with the ZnO/ZnCo2O4/C@rGO cathode catalyst displays a higher open circuit voltage and discharge voltage and more sluggish potential drop than those of the cell with the ZnO/ZnCo2O4/C cathode catalyst, which confirms that rGO can enhance the electrocatalytic activity and stability of the catalyst system. The excellent electrocatalytic performance of the ZnO/ZnCo2O4/C@rGO hybrid is attributed to the prominent conductivity and high specific surface area resulting from rGO, the more accessible catalytic active sites induced by the unique porous hollow nanocage structure, and synergic covalent coupling between rGO sheets and ZnO/ZnCo2O4/C nanocages.