Construction of Co1-x S Nanoparticles Embedding in N-Doped Amorphous Carbon@Graphene with Enhanced Li-Ion Storage.

Cobalt sulfide is deemed a promising anode material, owing to its high theoretical capacity (630 mAh g-1 ). Due to its low conductivity, fast energy decay, and the huge volume change during the lithiation process limits its practical application. In this work, a simple and large-scale method are developed to prepare Co1-x S nanoparticles embedding in N-doped carbon/graphene (CSCG). At a current density of 0.2 C, the reversible discharge capacity of CSCG maintains 937 mAh g-1 after 200 cycles. The discharge capacity of CSCG maintains at 596 mAh g-1 after 500 cycles at the high current density of 2.0 C. The excellent performance of CSCG is due to its unique structural features. The addition of rGO buffered volume changes while preventing Co1-x S from crushing/aggregating during the cycle, resulting in multiplier charge-discharge and long cycle life. The N-doped carbon provides a simple and easy way to achieve excellent performance in practical applications. Combined with density functional theory calculation, the presence of Co-vacancies(Co1-x ) increases more active site. Moreover, N-doping carbon is beneficial to the improve adsorption energy. This work presents a simple and effective structural engineering strategy and also provides a new idea to improve the performance of Li-ion batteries.

Synthesis of CoP@B,N,P co-doped porous carbon by a supramolecular gel self-assembly method for lithium-sulfur battery separator modification.

Lithium-sulfur batteries (LSBs) are regarded as promising next-generation batteries due to their high abundance and high theoretical energy density. However, the commercial application of LSBs is hindered by the shuttle effect of soluble lithium polysulfides (LiPSs). Hence, we synthesised B, N, P co-doped three-dimensional hierarchical porous carbon materials, uniformly dispersed with CoP nanoparticles, and utilized them as the coating material for the PE separator. The catalytic and adsorption capacity of the composite material was significantly enhanced by CoP. Both experimental and theoretical calculations show that the LiPS adsorption capacity of the composite material is significantly enhanced after the introduction of B atoms. As a result, the assembled LSBs with the CoP@BNPC/PE separator show excellent long-term stability (940.8 mA h g-1 after 500 cycles at 1.0 C, and only a 0.026% decay rate per cycle) and superior rate performance (613.6 mA h g-1 at 5.0 C). Our work further proves that a modified separator is an effective strategy to promote the commercialization of LSBs.

Rational Design of a Robust Flexible Triblock Polyurea Copolymer Protective Layer for High-Performance Lithium Metal Batteries.

Dendrite growth and volume expansion in lithium metal are the most important obstacles affecting the actual applications of lithium metal batteries. Herein, we design a robust flexible artificial solid electrolyte interphase layer based on a triblock copolymer polyurea film, which promotes uniform lithium deposition on the surface of the lithium metal electrode and has a high lithium-ion transference number. The high elasticity and close contact of polyurea compounds effectively suppress lithium dendrite growth and volume expansion in the Li anode, which are effectively confirmed by electrochemical characterization and optical microscopy observation. The symmetrical batteries with the PU-Li metal anode can achieve stable and reversible Li plating/stripping over 500 h at a current density of 5 mA cm-2. Matched with the high-mass-loaded S cathode and the commercial NCM523 cathode, this film significantly improves the cycle life of lithium metal batteries.

Composite Nanoarchitectonics with CoS2 Nanoparticles Embedded in Graphene Sheets for an Anode for Lithium-Ion Batteries.

Cobalt sulfides are attractive as intriguing candidates for anodes in Lithium-ion batteries (LIBs) due to their unique chemical and physical properties. In this work, CoS2@rGO (CSG) was synthesized by a hydrothermal method. TEM showed that CoS2 nanoparticles have an average particle size of 40 nm and were uniformly embedded in the surface of rGO. The battery electrode was prepared with this nanocomposite material and the charge and discharge performance was tested. The specific capacity, rate, and cycle stability of the battery were systematically analyzed. In situ XRD was used to study the electrochemical transformation mechanism of the material. The test results shows that the first discharge specific capacity of this nanocomposite reaches 1176.1 mAhg-1, and the specific capacity retention rate is 61.5% after 100 cycles, which was 47.5% higher than that of the pure CoS2 nanomaterial. When the rate changes from 5.0 C to 0.2 C, the charge-discharge specific capacity of the nanocomposite material can almost be restored to the initial capacity. The above results show that the CSG nanocomposites as a lithium-ion battery anode electrode has a high reversible specific capacity, better rate performance, and excellent cycle performance.

Ultrafast Kinetics in a PAN/MgFe2O4 Flexible Free-Standing Anode Induced by Heterojunction and Oxygen Vacancies.

Flexibility and power density are key factors restricting the development of flexible lithium-ion batteries (FLIBs). Interface and defect engineering can modify the intrinsic ion/electron kinetics by regulating the electronic structure. Herein, a polyacrylonitrile/MgFe2O4 (PAN-MFO) electrode with heterojunction and oxygen vacancies was first designed and synthesized as a flexible free-standing anode of FLIBs by electrostatic spinning technology. The PAN carbon nanofiber (PAN-CNF) as the skeleton structure provides fast conductive channels, buffers the volume expansion, and enhances the cycle stability. The heterostructure constructs the internal electric field, facilitates the Li+/charge transfer, intensifies the Li+ adsorption energy, and enhances the interfacial lithium storage. Oxygen vacancies improve the intrinsic conductivity, lower the Li+ diffusion barrier, weaken the Fe-O bonding, and facilitate the conversion reaction. Because of the synergistic effect of the multifunctional structure, the PAN-MFO shows superior cycle and rate performance with ultrafast kinetics. Flexible LiCoO2/PAN-MFO full pouch cells were also assembled that demonstrated a stable cycle performance and power supply in both the plain and bent states.

Study on the correlation between postoperative mental flexibility, negative emotions, and quality of life in patients with thyroid cancer.

BACKGROUND: In recent years, the global incidence of thyroid cancer has increased year by year. The purpose of this study is to investigate the post-surgical psychological flexibility and negative feelings of patients with thyroid cancer and their association with quality of life. METHODS: A total of 82 patients with thyroid cancer were selected. The study utilized the Acceptance and Action Questionnaire 2nd edition (AAQ-II), the Cognitive Fusion Questionnaire (CFQ), and the Meaning in Life Questionnaire-the Presence of Meaning (MLQ-P). By quantifying psychological flexibility, we assessed the patient's experiential avoidance, cognitive fusion, and sense of life meaning. The Self-rating Depression Scale (SDS) and the Self-rating Anxiety Scale (SAS) were employed to evaluate depression and anxiety, respectively. Quality of life was evaluated with the Functional Assessment of Cancer Therapy-General (FACT-G). RESULTS: The mean AAQ-II, CFQ, MLQ-P, SAS, and SDS scores were 20.1±9.2, 27.5±10.7, 23.0±5.7, 47.7±13.3, and 43.3±12.8, respectively. In total, 24.4% and 45.1% of patients had depression and anxiety to some extent, respectively. The AAQ-II and CFQ scores were positively correlated with the SDS and SAS scores, and negatively correlated with the FACT-G score. The MLQ-P score was inversely correlated with the SDS and SAS scores, and was positively correlated with the FACT-G score. Logistic regression analysis indicated that the AAQ-II, CFQ, and MLQ-P were independent risk factors for quality of life. CONCLUSIONS: Depression and anxiety are ubiquitous in patients with thyroid cancer following surgery. The psychological flexibility of patients is significantly negatively correlated with depression and anxiety and can dramatically influence quality of life.

In Situ Gel Polymer Electrolyte with Inhibited Lithium Dendrite Growth and Enhanced Interfacial Stability for Lithium-Metal Batteries.

The practical application of lithium-metal anodes in high-energy-density rechargeable lithium batteries is hindered by the uncontrolled growth of lithium dendrites and limited cycle life. An ether-based gel polymer electrolyte (GPE-H) is developed through in situ polymerization method, which has close contact with the electrode interface. Based on DFT calculations, it was confirmed that the cationic groups produced by polar solvent tris(1,1,1,3,3,3-hexafluoroisopropyl) (HFiP) initiate the ring-opening polymerization of DOL in the battery. As a result, GPE-H achieves considerable ionic conductivity (1.6 × 10-3 S cm-1) at ambient temperature, high lithium-ion transference number (tLi+ > 0.6) and an electrochemical stability window as high as 4.5 V. GPE-H can achieve up to 800 h uniform lithium plating/stripping at a current density of 1.65 mA cm-2 in Li symmetrical batteries. Li-S and LiFePO4 batteries using this GPE-H have long cycle performances at ambient temperature and high Coulomb efficiency (CE > 99.2%). From the above, in situ polymerized GPE-H electrolytes are promising candidates for high-energy-density rechargeable lithium batteries.

Multifunctional organosilicon compound contributes to stable operation of high-voltage lithium metal batteries.

With the increasing demand for high-energy-density energy storage devices, lithium metal batteries have rekindled the interest of researchers due to ultra-high specific capacity. However, the extremely unstable interfaces between the electrolyte and electrodes limit its application seriously. Herein, we introduce an organosilicon compound, 1,3-Divinyltetramethyldisiloxane (DTMDS), as multifunctional electrolyte additive to enhance the performance of LiNi0.5Mn1.5O4/Li batteries. DTMDS contains two functional groups: siloxane groups (Si-O) and unsaturated carbon-carbon double bonds (CC). Siloxane groups can capture hydrogen fluoride (HF) in electrolyte, and the carbon-carbon double bonds can form thin and dense passivation layer on both cathode and anode surfaces by polymerization. As a result, the capacity retention of the batteries can retain more than 95% after 500 cycles. This work provides a valuable reference for the design of multifunctional additives and stabilizing the interfaces of high-voltage lithium metal batteries.

Fluorophosphorus derivative forms a beneficial film on both electrodes of high voltage lithium-ion batteries.

Layered lithium-rich oxides, as a series of highly promising cathode material for lithium-ion batteries, attract extensive attention due to their high specific capacity and high working potential (4.6 V vs Li/Li+). However, the poor interface stability of the cathode and electrolyte seriously restricts their practical application. In this article, theoretical calculations, linear sweep voltammetry and cyclic voltammetry results indicate that tris (pentafluorophenyl) phosphine (TPFPP) is a potential dual-functional electrolyte additive to solve interface problems. The TPFPP additive can decompose preferentially on the surface of both electrodes and form uniform and stable protective films, which effectively inhibit the continuous decomposition of the electrolyte and significantly alleviate the dissolution of transition metal ions during cycling. Owing to the above effects, the capacity retention and coulombic efficiency of Li1.17Ni0.25Mn0.58O2 (LLO)/graphite (Gr) cells are improved from 62.6% and 97.7% to 90.6% and 99.8% after 200 cycles at 0.3 C (1 C = 300 mA g-1), respectively. This study provides a wide prospect for the application of lithium-rich materials in the future.

A soluble single atom catalyst promotes lithium polysulfide conversion in lithium sulfur batteries.

CoPcCl is used as a catalytic electrolyte additive for lithium sulfur batteries under the guidance of theoretical calculations. The electrolyte additive strategy is easier to realize and more effective compared with the fabrication of catalytic host materials. Adding CoPcCl in the electrolyte enhanced the sulfur utilization remarkably.

Biomimetic Synthesis of Polydopamine Coated ZnFe2O4 Composites as Anode Materials for Lithium-Ion Batteries.

Metal oxides as anode materials for lithium storage suffer from poor cycling stability due to their conversion mechanisms. Here, we report an efficient biomimetic method to fabricate a conformal coating of conductive polymer on ZnFe2O4 nanoparticles, which shows outstanding electrochemical performance as anode material for lithium storage. Polydopamine (PDA) film, a bionic ionic permeable film, was successfully coated on the surfaces of ZnFe2O4 particles by the self-polymerization of dopamine in the presence of an alkaline buffer solution. The thickness of PDA coating layer was tunable by controlling the reaction time, and the obtained ZnFe2O4/PDA sample with 8 nm coating layer exhibited an outstanding electrochemical performance in terms of cycling stability and rate capability. ZnFe2O4/PDA composites delivered an initial discharge capacity of 2079 mAh g-1 at 1 A g-1 and showed a minimum capacity decay after 150 cycles. Importantly, the coating layer improved the rate capability of composites compared to that of its counterpart, the bare ZnFe2O4 particle materials. The outstanding electrochemical performance was because of the buffering and protective effects of the PDA coating layer, which could be a general protection strategy for electrode materials in lithium-ion batteries.

Bio-Inspired Synthesis of an Ordered N/P Dual-Doped Porous Carbon and Application as an Anode for Sodium-Ion Batteries.

Carbonaceous materials are one of the most promising anode materials for sodium-ion batteries, because of their abundance, stability, and safe usage. However, the practical application of carbon materials is hindered by poor specific capacity and low initial Coulombic efficiency. The design of porous structure and doping with heteroatoms are two simple and effective methods to promote the sodium storage performance. Herein, the N, P co-doped porous carbon materials are fabricated using renewable and biodegradable gelatin as carbon and nitrogen resource, phosphoric acid as phosphorus precursor and polystyrene nanospheres as a template. The product can deliver a reversible capacity of 230 mA h g-1 at a current density of 0.2 A g-1 , and even a high capacity of 113 mA h g-1 at 10 Ag-1 . The enhanced sodium storage performance is attributed to the synergistic effect of the porosity and the dual-doping of nitrogen and phosphorus.

MOF-derived cobalt-doped ZnO@C composites as a high-performance anode material for lithium-ion batteries.

Cobalt (Co)-doped MOF-5s (Co-MOF-5s) were first synthesized by a secondary growth method, followed by a heat treatment to yield Co-doped ZnO coated with carbon (CZO@C). Compared with carbon-coated ZnO (ZnO@C), the doping of Co increased the graphitization degree of the carbon on the surface of CZO@C nanoparticles and enhanced the conductivity of the material. The electrochemical properties of the materials were characterized by galvanostatic discharge/charge tests. It was found that the as-synthesized CZO@C composites enabled a reversible capacity of 725 mA h g(-1) up to the 50th cycle at a current density of 100 mA g(-1), which was higher than that of ZnO@C composites (335 mA h g(-1)).

[Meta-analysis of fibrin glue for attaching conjunctival autografts in pterygium surgery].

OBJECTIVE: To evaluate the clinical efficacy of FG for attaching conjunctival autografts in pterygium surgery. METHODS: Search was conducted in Pubmed, EMbase, Cochrane Library, CNKI, Wanfang database, CBM and VIP, and hand-search was also performed, the methodological quality were carried out according to evidence-based medicine (EBM). The qualities of the randomized controlled trials (RCT) were evaluated according to the Cochrane Handbook for Systematic Reviews of Interventions Version 5.0. The Cochrane Collaboration's software RevMan 5.0 was used for Meta-analysis. RESULTS: Only 7 trials, involving 366 eyes, were included. Meta-analysis showed that significant differences were found between the FG and suture in recurrence [RR = 0.34, 95%CI (0.15, 0.80), P = 0.01], but there is no difference in reducing the complications [RR = 2.53, 95%CI (0.47, 13.51), P = 0.28]. CONCLUSION: Fibrin glue-assisted conjunctival autograft in pterygium surgery reduces postoperative recurrence.

[Effect of Nogo-66 on retinal microglia in chronic ocular hypertension rats].

OBJECTIVE: To study the effect of protein Nogo-66 on the expression of CD11b and MHC-II in retinal microglia of chronic ocular hypertension SD rats and the effects of protein Nogo-66 on the immunogenicity of injured retinal tissues. METHODS: It was a control experimental study. Chronic ocular hypertension rat model was established by laser photocoagulation on the anterior chamber angle and superficial vein of the sclera. One ml of Nogo-66 (0.01%) in PBS was injected subcutaneously on the day of laser treatment and 0.005% Nogo-66 PBS solution was injected into the vitreous 7 days and 1 month latter. PBS without Nogo-66 was injected in the control group. The expression of cell surface antigen CD11b and MHC-II were detected by immunohistochemistry 1 month and 1 day after the establishment of hypertension model. The difference of average IOP among groups was analyzed by variance analysis. The difference of expression of CD11b and MHC-II between the experimental and control groups was analyzed by t-test. RESULTS: The intraocular pressure (IOP) of experimental groups rised from the seventh day after model-building and the highest IOP was (24.16 ± 2.70) mm Hg (1 mm Hg = 0.133 kPa) 1 month later while that in the control groups was (15.93 ± 3.28) mm Hg. The difference between them was statistically significant (F = 2.10, P < 0.05). Expression of CD11b was (1.78 ± 0.63)% and MHC-II was (3.92 ± 1.03)% in Nogo-66 with hypertension groups, these results was significantly lower than those in Nogo-66 with normal intraocular pressure groups in which the expression of CD11b was (8.15 ± 1.97)% (t = 2.35, P < 0.05) and MHC-II was (11.45 ± 1.97)% (t = 2.14, P < 0.05). CONCLUSIONS: Protein Nogo-66 activated the cell surface antigen CD11b in nerve fiber layer of retina and induced antigen presenting molecules (MHC-II). This indicates that Nogo has the center immunogenicity and this protein could activate antigen-presenting cells to present injury antigen.

A new staging system is more discriminant than conventional staging systems for unresectable hepatocellular carcinoma.

BACKGROUND: Prediction of the life expectancy of a patient with unresectable hepatocellular carcinoma (HCC) remains difficult. The aims of the study were to construct a new staging scheme for patients with unresectable HCC and to compare the discriminatory ability of the staging scheme with the Okuda and CLIP score and TNM staging system in a cohort of patients with unresectable HCC. METHODS: A retrospective analysis of unresectable HCC cases from 1999 to 2003 was performed. The Cox model was used for multivariate analyses. The final model was derived from 10 randomly chosen training samples and the prognostic validity of the new staging scheme was assessed on the corresponding testing samples. Moreover, 54 cases with unresectable HCC were enrolled and prospectively followed up. The new staging, named the China integrated score (CIS), Okuda, TNM and CLIP systems were determined for each case. Comparisons of the survival rate between each stage were performed to evaluate their discriminatory ability. RESULTS: A simple scoring system was constructed, assigning linear scores (0/1/2) to the three covariates (TNM, alpha-fetoprotein and Child-Pugh) of the final model. The CIS system was more discriminant than the Okuda or TNM staging system, as confirmed by the Kaplan-Meier comparison of survival curves and by the Cox's regression analysis, with a median survival rate of 9.0, 2.3, 2.1 and 0.6 months in patients with CIS 2, 3, 4 and 5, respectively. The CIS system was performed as well as the CLIP score. CONCLUSION: The new staging system, accounting for both liver function and tumor characteristics, can accurately identify patients with different prognoses, particularly in the advanced phases of HCC. It should be useful as the only tool that can be applied for patients with unresectable HCC.

[Expression of CD11b in the retinal microglia in chronic hypertension rat].

OBJECTIVE: To study the expression of CD11b in the retinal microglia in laser induced ocular hypertension (OHT) SD rat. METHODS: It was an experimental study. OHT was induced by the coagulation of trabecular meshwork using 532-laser in sixty SD rats. Intraocular pressure (IOP) was measured by Tonopen-XL, the expression of CD11b in retinal microglia detected by immunohistochemistry, and retinal ganglion cells (RGCs) were labeled with Dextran Tetramethyl Rhodamine (DTR) and counted by Image-Pro Plus Version 6.0 image analysis software at 2 weeks, 1, 2, 3, 4, 5, and 6 months, respectively. All the numerical data were statistically analyzed by SPSS 13.0 software. RESULTS: Although the IOP of experimental groups are still the similar level at 2w after coagulation (t = 1.124, P = 0.287), Compared to control eyes, IOP in lasered eyes was significantly (t = 2.487, P = 0.036) increased at 1 month, lasting for 3 months and returned to normal from 5 to 6 months (t = 1.103, P = 0.290). The expression of CD11b in the retinal microglia in the lasered eyes was significantly more intensive than that in control eyes at 1 month (t = 3.333, P = 0.008) and faded after 5 months, a similar pattern to IOP response, that two group data shows significant dependability (r = 0.891, P = 0.014). The number of RGC was significantly reduced from 1 month to 6 months (t = 3.316, P = 0.009), the velocity of reducing seems dependability to the advancing of IOP (r = 0.757, P = 0.021). CONCLUSIONS: The expression of CD11b in retinal microglia is fluctuated with chronic OHT pattern and RGCs injury level indicating that the injury antigens by microglia are presented in the retina with the increase of IOP and activate the immunologic process leading to glaucomatous RGCs damage. It suggests that it is important to effectively control the IOP in order to reduce the risk of immune induced retinal damage by microglia.