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In order to improve the mechanical properties of 40Cr steel, a Ni/Co - TiN nanocoating was prepared on its surface by ultrasonic jet electrodeposition. The surface morphology, phase structure and elemental composition of the coating were observed by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and x - ray diffractometer (XRD). Moreover, the microhardness, wear resistance and corrosion resistance of coating were tested by microhardness tester, friction and wear tester and electrochemical workstation. Results showed that the microhardness of the Ni/Co - TiN nanocoating increased first and then decreased with the rising of the concentration of TiN nanoparticle, the jet speed of plating solution or the ultrasonic power. From the orthogonal experiment results, it could be obtained that the optimal process parameters were a jet speed of the plating solution of 4 m/s, an ultrasonic power of 120 W, and a concentration of TiN nanoparticle of 10 g/L. The Ni/Co grain sizes in the coating prepared using the optimal process parameters were obviously refined, TiN particles were dispersed in the coating, and the appearance of the coating was smooth and dense. Moreover, the microhardness of the coating was up to 689.82 HV, the friction coefficient was small, and the weight loss was small. The self - corrosion potential (Ecorr) and self - corrosion current density (Jcorr) were -0.338 V and 2.13×10-6 A/cm2, respectively.

Charging the LiCoO2 (LCO) cathode to a higher voltage, for example 4.5 V compared to the commonly used 4.2 V, is now intensively pursued so as to achieve a higher specific capacity. However, it suffers severe surface structural degradation and detrimental interfacial side reactions between cathode and electrolyte, which lead to the fast capacity fading during long-term cycling. Here, a surface coating strategy was developed for the protection of 4.5 V LCO by constructing a manganese oxides (MOs) nanoshell around LCO particles, which was achieved through a solution-based coating process with success in controlling the growth kinetics of the coating species. We found that the introduction of the MOs nanoshell is highly effective in alleviating the organic electrolyte decomposition at the cathode surface, thus ensuring a much more stable LiF-rich cathode-electrolyte interface and an obvious lower interfacial resistance during electrochemical cycling. Meanwhile, this protection layer can effectively improve the structural stability of the cathode by hindering the cracks formation and structural degradation of LCO particles. Therefore, the MOs modified LCO exhibited excellent rate performance and a high discharge capacity retention of 81.5% after 100 cycles at 1 C compared with the untreated LCO (55.2%), as well as the improved thermal stability and cyclability at the elevated temperature. It is expected that this discovery and fundamental understanding of the surface chemistry regulation strategy provide promising insights into improving the reversibility and stability of LCO cathode at the cut-off voltage of 4.5 V. [ABSTRACT FROM AUTHOR]

Solid‐state batteries (SSBs) are promising for next‐generation energy storage with advantages in both energy density and safety, but are challenged by the poor solid‐to‐solid contact between solid‐state electrolytes (SSEs) and electrodes, particularly the lithium anode. Herein, a facile coordination‐assisted deposition process is employed to build artificial Ta2O5 nanofilms on SSEs, which is lithiophilic and has high stability against metallic lithium, thereby ensuring an intimate and stable interface between SSEs and lithium anode to sustain extended cycles. The feasibility is verified by using Li6.5La3Zr1.5Ta0.5O12 (LLZT), a garnet‐typed SSEs, as a model system. It is shown that a 12 nm Ta2O5 nanofilm is able to significantly decrease the interfacial resistance from 1258 to 9 Ω cm2 with a high critical current density reaching 2.0 mA cm−2 for the assembled symmetric cell, which shows an unprecedented capability to survive long‐term cycling over 5200 h. This control strategy is also able to enable the use of the commercialized cathode materials of LiFePO4 and LiNi0.83Co0.07Mn0.1O2 in SSBs with both high reversible capacity and cycling capability. The study opens up a research avenue for the delicately carved interlayers through a scalable and reliable manufacturing process which can accelerate the commercialization of SSEs. [ABSTRACT FROM AUTHOR]

Layered LiCoO2 (LCO) is one of the most important cathodes for portable electronic products at present and in the foreseeable future. It becomes a continuous push to increase the cutoff voltage of LCO so that a higher capacity can be achieved, for example, a capacity of 220 mAh g–1 at 4.6 V compared to 175 mAh g–1 at 4.45 V, which is unfortunately accompanied by severe capacity degradation due to the much‐aggravated side reactions and irreversible phase transitions. Accordingly, strict control on the LCO becomes essential to combat the inherent instability related to the high voltage challenge for their future applications. This review begins with a discussion on the relationship between the crystal structures and electrochemical properties of LCO as well as the failure mechanisms at 4.6 V. Then, recent advances in control strategies for 4.6 V LCO are summarized with focus on both bulk structure and surface properties. One closes this review by presenting the outlook for future efforts on LCO‐based lithium ion batteries (LIBs). It is hoped that this work can draw a clear map on the research status of 4.6 V LCO, and also shed light on the future directions of materials design for high energy LIBs. [ABSTRACT FROM AUTHOR]

Layered LiCoO 2 (LCO) is one of the most important cathodes for portable electronic products at present and in the foreseeable future. It becomes a continuous push to increase the cutoff voltage of LCO so that a higher capacity can be achieved, for example, a capacity of 220 mAh g -1 at 4.6 V compared to 175 mAh g -1 at 4.45 V, which is unfortunately accompanied by severe capacity degradation due to the much-aggravated side reactions and irreversible phase transitions. Accordingly, strict control on the LCO becomes essential to combat the inherent instability related to the high voltage challenge for their future applications. This review begins with a discussion on the relationship between the crystal structures and electrochemical properties of LCO as well as the failure mechanisms at 4.6 V. Then, recent advances in control strategies for 4.6 V LCO are summarized with focus on both bulk structure and surface properties. One closes this review by presenting the outlook for future efforts on LCO-based lithium ion batteries (LIBs). It is hoped that this work can draw a clear map on the research status of 4.6 V LCO, and also shed light on the future directions of materials design for high energy LIBs., (© 2022 Wiley-VCH GmbH.)

Aim: To investigate the association between thrombocytopenia and relapse after treatment for hepatocellular carcinoma (HCC)., Methods: We searched the PubMed, EMBASE, and Web of Science databases to obtain eligible studies. The hazard ratios (HRs) values and 95% confidence intervals (CIs) were pooled by random effects model. Subsequently, we estimated the heterogeneity, performed a sensitivity analysis, determined the publication bias, and performed subgroup and meta-regression analyses. Study quality was assessed by using the Oxford Center for Evidence Based Medicine tool., Results: We identified 18 eligible studies by retrieval (published during 2000-2014). Out of the 4163 patients with HCC who were recruited, 2746 (66.0%) experienced recurrence. In general, our meta-analysis suggested that low platelet count (PLT) before therapy significantly increased the probability of postoperative recurrence (HR = 1.53, 95%CI: 1.29-1.81). PLT was also valuable in the prediction of intrahepatic distant recurrence (HR = 1.49, 95%CI: 1.25-1.77). Subgroup and meta-regression analyses identified various therapeutic modalities as the source of a high degree of heterogeneity. The pooled HR values showed no obvious change when a single study was removed, but otherwise, an opposite-effects model was used. In addition, no significant publication bias was detected., Conclusion: Thrombocytopenia before treatment might be an inexpensive and useful predictor of postoperative recurrence in patients with HCC.

Aim: To investigate the hepatoprotective effects and mechanisms of hydrogen-rich water (HRW) in acetaminophen (APAP)-induced liver injury in mice., Methods: Male mice were randomly divided into the following four groups: normal saline (NS) control group, mice received equivalent volumes of NS intraperitoneally (ip); HRW control group, mice were given HRW (same volume as the NS group); APAP + NS group, mice received NS ip for 3 d (5 mL/kg body weight, twice a day at 8 am and 5 pm) after APAP injection; APAP + HRW group, mice received HRW for 3 d (same as NS treatment) after APAP challenge. In the first experiment, mice were injected ip with a lethal dose of 750 mg/kg APAP to determine the 5-d survival rates. In the second experiment, mice were injected ip with a sub-lethal dose of 500 mg/kg. Blood and liver samples were collected at 24, 48, and 72 h after APAP injection to determine the degree of liver injury., Results: Treatment with HRW resulted in a significant increase in the 5-d survival rate compared with the APAP + NS treatment group (60% vs 26.67%, P < 0.05). HRW could significantly decrease the serum alanine aminotransferase level (24 h: 4442 ± 714.3 U/L vs 6909 ± 304.8 U/L, P < 0.01; 48 h: 3782 ± 557.5 U/L vs 5111 ± 404 U/L, P < 0.01; and 3255 ± 337.4 U/L vs 3814 ± 250.2 U/L, P < 0.05, respectively) and aspartate aminotransferase level (24 h: 4683 ± 443.4 U/L vs 5307 ± 408.4 U/L, P < 0.05; 48 h: 3392 ± 377.6 U/L vs 4458 ± 423.6 U/L, P < 0.01; and 3354 ± 399.4 U/L vs 3778 ± 358 U/L, respectively) compared with the APAP treatment group. The alkaline phosphatase, total bilirubin and lactate dehydrogenase levels had the same result. Seventy-two hours after APAP administration, liver samples were collected for pathological examination and serum was collected to detect the cytokine levels. The liver index (5.16% ± 0.26% vs 5.88% ± 0.073%, P < 0.05) and percentage of liver necrosis area (27.73% ± 0.58% vs 36.87% ± 0.49%, P < 0.01) were significantly lower in the HRW-treated animals. The malonyldialdehyde (MDA) contents were significantly reduced in the HRW pretreatment group, but they were increased in the APAP-treated group (10.44 ± 1.339 nmol/mg protein vs 16.70 ± 1.646 nmol/mg protein, P < 0.05). A decrease in superoxide dismutase (SOD) activity in the APAP treatment group and an increase of SOD in the HRW treatment group were also detected (9.74 ± 0.46 U/mg protein vs 12.1 ± 0.67 U/mg protein, P < 0.05). Furthermore, HRW could significantly increase the glutathione (GSH) contents (878.7 ± 76.73 mg/g protein vs 499.2 ± 48.87 mg/g protein) compared with the APAP treatment group. Meanwhile, HRW could reduce the inflammation level (serum TNF-α: 399.3 ± 45.50 pg/L vs 542.8 ± 22.38 pg/L, P < 0.05; and serum IL-6: 1056 ± 77.01 pg/L vs 1565 ± 42.11 pg/L, P < 0.01, respectively). In addition, HRW could inhibit 4-HNE, nitrotyrosine formation, JNK phosphorylation, connexin 32 and cytochrome P4502E expression. Simultaneously, HRW could facilitate hepatocyte mitosis to promote liver regeneration., Conclusion: HRW has significant therapeutic potential in APAP-induced hepatotoxicity by inhibiting oxidative stress and inflammation and promoting liver regeneration.

Aim: To investigate whether central obesity is associated with nonalcoholic fatty liver disease (NAFLD) formation after adjusting for general obesity., Methods: The online databases PubMed, EMBASE, and ISI Web of Science were searched for studies estimating the influence of central obesity on NAFLD occurrence published through April 2014. Studies that did not adjust for body mass index (BMI) were excluded. In addition, the independent effect of BMI was also assessed with the included studies. The pooled effect sizes and 95% confidence intervals (CIs) were calculated using random- or fixed-effects models based on the degree of heterogeneity. Furthermore, subgroup analyses, meta-regression, sensitivity analyses, and publication bias were performed., Results: Twenty eligible studies were identified. The summary odds ratio (OR) values per-unit increase in waist circumference (WC) and BMI for NAFLD formation were 1.07 (95%CI: 1.03-1.10, I (2) = 73.9%, n = 11 studies) and 1.25 (95%CI: 1.13-1.38, I (2) = 88.7%, n = 11 studies), respectively. When the indices were expressed as binary variables (with the non-obesity group as reference), the pooled OR in WC, waist-to-hip ratio, and BMI were 2.34 (95%CI: 1.83-3.00, I (2) = 41.8%, n = 7 studies), 4.06 (95%CI: 1.53-10.79, I (2) = 65.7%, n = 3 studies), and 2.85 (95%CI: 1.60-5.08, I (2) = 57.8%, n = 5 studies), respectively. Using the same studies as the latter (n = 5), pooled OR in WC was 3.14 (95%CI: 2.07-4.77), which is greater than that in BMI., Conclusion: Central obesity may pose a greater threat to national health than general obesity, although both are independently associated with increased risk of NAFLD.