A Review on Regenerating Materials from Spent Lithium-Ion Batteries.

Recycling spent lithium-ion batteries (LIBs) have attracted increasing attention for their great significance in environmental protection and cyclic resources utilization. Numerous studies focus on developing technologies for the treatment of spent LIBs. Among them, the regeneration of functional materials from spent LIBs has received great attention due to its short process route and high value-added product. This paper briefly summarizes the current status of spent LIBs recycling and details the existing processes and technologies for preparing various materials from spent LIBs. In addition, the benefits of material preparation from spent LIBs, compared with metals recovery only, are analyzed from both environmental and economic aspects. Lastly, the existing challenges and suggestions for the regeneration process are proposed.

Enzymes encapsulated in organic-inorganic hybrid nanoflower with spatial localization for sensitive and colorimetric detection of formate.

Formate is an important environmental pollutant, and meanwhile its concentration change is associated with a variety of diseases. Thus, rapid and sensitive detection of formate is critical for the biochemical analysis of complex samples and clinical diagnosis of multiple diseases. Herein, a colorimetric biosensor was constructed based on the cascade catalysis of formate oxidase (FOx) and horseradish peroxidase (HRP). These two enzymes were co-immobilized in Cu3(PO4)2-based hybrid nanoflower with spatial localization, in which FOx and HRP were located in the shell and core of nanoflower, respectively (FOx@HRP). In this system, FOx could catalyze the oxidation of formate to generate H2O2, which was then utilized by HRP to oxidize 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid to yield blue product. Ideal linear correlation could be obtained between the absorbance at 420 nm and formate concentration. Meanwhile, FOx@HRP exhibited excellent detection performance with low limit of detection (6 µM), wide linear detection range (10-900 µM), and favorable specificity, stability and reusability. Moreover, it could be applied in the detection of formate in environmental, food and biological samples with high accuracy. Collectively, FOx@HRP provides a useful strategy for the simple and sensitive detection of formate and is potentially to be used in biochemical analysis and clinical diagnosis.

Stress load and volunteer motivation of patient volunteers in Fangcang shelter hospitals in Shanghai, China during the COVID-19 pandemic: a cross-sectional survey.

OBJECTIVES: This study aims to assess the volunteer motivation and stress load of patient volunteers in the Fangcang shelter hospitals (FSHs), examine their associations, and explore the potential influence factors of volunteer motivation. DESIGN: Cross-sectional online survey conducted from 21 April to 20 May 2022. SETTING: Questionnaires were collected from patient volunteers selected by random cluster sampling in the FSHs in Shanghai, China. PARTICIPANTS: 197 participants who met the inclusion criteria as patients who were asymptomatic or presenting with mild symptoms in the FSHs and who volunteered to assist with routine work under quarantined settings. OUTCOME MEASURES: We investigated sociodemographic information, stress load and volunteer motivation through an online survey using the Volunteer Function Inventory and the Stress Overload Scale. Comparisons between groups were conducted by applying t-tests or analysis of variance. The correlation between volunteer motivation and stress was analysed by Pearson correlation. Influencing factors of volunteer motivation were determined by multivariable linear regression models. A value of p<0.05 was used to declare statistical significance. RESULTS: The mean score of volunteer motivation of patient volunteers was 73.24 (SD 12.00), while that of stress load was 46.08 (SD 21.28). The mean scores of the personal vulnerability (PV) and event load (EL), two dimensions of stress load, were 26.99 (SD 12.46) and 19.09 (SD 9.63), respectively. The majority of the participants (136, 69.04%) were grouped in the low (PV)-low (EL) stress category. Participants' volunteer motivation was negatively correlated with stress load (r=-0.238, p<0.001), as well as PV (r=-0.188, p<0.01) and EL (r=-0.283, p<0.001). Multivariable linear regression analysis identified that the potential influencing factors of volunteer motivation were occupation (B=1.100, 95% CI 0.037 to 2.164, p=0.043), health condition (B=-3.302, 95% CI -5.287 to -1.317, p<0.001) and EL (B=-0.434, 95% CI -0.756 to -0.111, p=0.009). Participants who worked in the public sector, had better health conditions and had lower EL were more likely to have higher volunteer motivation. CONCLUSIONS: Our study suggested that reducing stress load might be a possible pathway to encourage and maintain volunteerism in the FSH context. Implications and suggestions for future research on patient volunteer recruitment and management could be drawn from our findings.

Transient Liquid Phase Diffusion Bonding of Ni3Al Superalloy with Low-Boron Nickel-Base Powder Interlayer.

As a technology for micro-deformed solid-phase connection, transient liquid phase (TLP) diffusion bonding plays a key role in the manufacture of heating components of aero engines. However, the harmful brittle phase and high hardness limit the application of TLP diffusion bonding in nickel-based superalloys. In this paper, a new strategy in which a low-boron and high-titanium interlayer can restrain the brittle phase and reduce the hardness of the TLP-diffusion-bonded joint is proposed. With this strategy, the Ni3Al joint can achieve a high strength of 860.84 ± 26.9 MPa under conditions of 1250 °C, 6 h and 5 MPa. The microhardness results show that the average microhardness of the joint area is 420.33 ± 3.15 HV and is only 4.3% higher than that of the Ni3Al base material, which proves that this strategy can effectively inhibit the formation of the harmful brittle phase in the joint area. The results of EBSD show that 7.7% of the twin boundaries exist in the isothermal solidification zone, and only small amounts of secondary precipitates are observed at the grain boundaries in the joint, which indicates that twin boundaries may play a dominant role in crack initiation. This study provides a feasible avenue to suppress the brittle phase in TLP-diffusion-bonded joints.

Stress Concentration Induced by the Crystal Orientation in the Transient-Liquid-Phase Bonded Joint of Single-Crystalline Ni3Al.

Single-crystalline Ni3Al-based superalloys have been widely used in aviation, aerospace, and military fields because of their excellent mechanical properties, especially at extremely high temperatures. Usually, single-crystalline Ni3Al-based superalloys are welded together by a Ni3Al-based polycrystalline alloy via transient liquid phase (TLP) bonding. In this study, the elastic constants of single-crystalline Ni3Al were calculated via density functional theory (DFT) and the elastic modulus, shear modulus, and Poisson's ratio of the polycrystalline Ni3Al were evaluated by the Voigt-Reuss approximation method. The results are in good agreement with previously reported experimental values. Based on the calculated mechanical properties of single-crystalline and polycrystalline Ni3Al, three-dimensional finite element analysis (FEA) was used to characterize the mechanical behavior of the TLP bonded joint of single-crystalline Ni3Al. The simulation results reveal obvious stress concentration in the joint because of the different states of crystal orientation between single crystals and polycrystals, which may induce failure in the polycrystalline Ni3Al and weaken the mechanical strength of the TLP bonded joint. Furthermore, results also show that the decrease in the elastic modulus of the intermediate layer (i.e., polycrystalline Ni3Al) can relieve the stress concentration and improve the mechanical strength in the TLP bonded joint.

Determination of specific IgG4 for diagnosis and therapeutic evaluation of cerebral cysticercosis.

OBJECTIVE: To probe the significance of specific IgG4 in sera of patients with cerebral cysticercosis for diagnosis and therapeutic evaluation. METHODS: Specific IgG4 in sera of patients with cerebral cysticercosis was assessed using colloidal gold-labeled mouse-anti-human IgG4 McAb as probe. The results were compared with the CT image manifestation. RESULTS: The specific IgG4 positive rate in sera of patients with cerebral cysticercosis was 97.8%, whereas sera from patients with other kinds of parasitosis or central nerve system disease and the control group were all negative, except for a weak cross-reaction of sera from patients with hepatic echinococoosis. The determination of specific IgG4 in sera of patients with cerebral cysticercosis during different times of treatment showed that along with an increase in treatment time and improvement of clinical symptoms, specific IgG4 level gradually decreased. The positive rate and intensity of specific IgG4 in sera from patients with cerebral cysticercosis were consistent with the number of cysticercus parasites in the brain and pathologic changes, such as survival, disintegration, death and calcification. Survival of cysticercus in the brain was objectively evaluated using this technique. CONCLUSIONS: The determination of specific IgG4 in sera is a practical method for diagnosis and therapeutic evaluation of cerebral cysticercosis.

Rapidly tuning miniature transversely excited atmospheric-pressure CO2 laser.

An experimental study of a rapidly tuning miniature transversely excited atmospheric-pressure CO2 laser is reported. To rapidly shift laser wavelengths over selected transitions in the 9-11 microm wavelength region, we have utilized a high-frequency stepping motor and a diffraction grating. The laser is highly automated with a monolithic microprocessor controlled laser line selection. For the achievement of stable laser output, a system of laser excitation with a voltage of 10 kV, providing effective surface corona preionization and allowing one to work at various gas pressures, is utilized. Laser operation at 59 emission lines of the CO2 molecule rotational transition is obtained and at 51 lines, the pulse energy of laser radiation exceeds 30 mJ. The system can be tuned between two different rotational lines spanning the wavelength range from 9.2 to 10.8 microm within 10 ms.