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1.
Sci Total Environ ; 929: 172558, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38643884

RESUMO

Compost-based organic fertilizers often contain high levels of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs). Previous studies focused on quantification of total ARGs and MGEs. For a more accurate risk assessment of the dissemination risk of antibiotic resistance, it is necessary to quantify the intracellular and extracellular distribution of ARGs and MGEs. In the present study, extracellular ARGs and MGEs (eARGs and eMGEs) and intracellular ARGs and MGEs (iARGs and iMGEs) were separately analyzed in 51 commercial composts derived from different raw materials by quantitative polymerase chain reaction (qPCR) and metagenomic sequencing. Results showed that eARGs and eMGEs accounted for 11-56% and 4-45% of the total absolute abundance of ARGs and MGEs, respectively. Comparable diversity, host composition and association with MGEs were observed between eARGs and iARGs. Contents of high-risk ARGs were similar between eARGs and iARGs, with high-risk ARGs in the two forms accounting for 6.7% and 8.2% of the total abundances, respectively. Twenty-four percent of the overall ARGs were present in plasmids, while 56.7% of potentially mobile ARGs were found to be associated with plasmids. Variation partitioning analysis, null model and neutral community model indicated that the compositions of both eARGs and iARGs were largely driven by deterministic mechanisms. These results provide important insights into the cellular distribution of ARGs in manure composts that should be paid with specific attention in risk assessment and management.


Assuntos
Resistência Microbiana a Medicamentos , Fertilizantes , Resistência Microbiana a Medicamentos/genética , Microbiologia do Solo , Compostagem , Genes Bacterianos
2.
Chem Commun (Camb) ; 60(19): 2669-2672, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38351890

RESUMO

Reported herein is a photochemical strategy for C(sp3)-H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N-alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ.

3.
Ther Adv Neurol Disord ; 17: 17562864231219151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38288324

RESUMO

Background: Due to the rarity of polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome, the best first-line treatment has not been established, although there are several options in guidelines. The preferred treatments vary according to the preference of the physician and anecdote. Objectives: First, to analyze the efficacy of a new treatment mode in POEMS syndrome that uses the four-cycle treatment as the induction regimen, followed by sequential transplantation as the consolidation regimen for transplantation-eligible patients, or received another two-cycle treatment for transplantation-ineligible patients. Second, to compare the efficacy and safety of regimens with a proteasome inhibitor (bortezomib-cyclophosphamide-dexamethasone, BCD) or without a proteasome inhibitor (cyclophosphamide-dexamethasone ± thalidomide, CD ± T). Design: We conducted a retrospective study using real-world data from Capital Medical University, Xuanwu Hospital. Methods: A total of 34 newly diagnosed POEMS syndrome patients met Dispenzieri's diagnostic criteria, and those who completed at least four cycles of treatment from July 2013 to March 2021 were included. Results: The overall vascular endothelial growth factor (VEGF) response rate of this new treatment mode was 100%. The cumulative VEGF complete remission (CRV) rate was 67.9%, and the cumulative complete hematological response (CRH) rate was 55.6%. During the median 49-month follow-up, the 5-year-overall survival (OS) rate was 90.7%, the 3-year-progression-free survival (PFS) rate was 78.4%, and the 5-year-PFS rate was 73.8%. The BCD regimen achieved a 75% CRV rate (median time from diagnosis to CRV = 130 days) and 66.7% CRH rate (median time from diagnosis to CRH = 218 days). In addition, the VEGF response was less than the partial remission (PRV) after four-cycle induction treatment, which, together with a decrease on the Overall Neurological Limitation Scale of less than three points 1 year after consolidation treatment, was an independent poor prognostic factor. Conclusion: Bortezomib was well-tolerated by patients with POEMS syndrome. Compared with CD ± T regimen, BCD as the induction regimen achieved better VEGF response and earlier hematological remission. Autologous stem cell transplantation used as consolidation therapy further improved the neurological and hematological remission rates, resulting in better OS and PFS.

5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 149-154, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36861169

RESUMO

Acute coronary syndrome (ACS),with increasing mortality year by year,has become a major public health problem in China.Exercise rehabilitation as an important part of the out-of-hospital rehabilitation for the patients with heart diseases can further reduce the mortality of patients on the basis of drug treatment.The available studies have proved that high-intensity interval training (HIIT) is more effective and efficient than moderate-intensity continuous training (MICT) such as walking and jogging on chronic cardiovascular diseases such as heart failure,stable coronary heart disease,and hypertension and has high security.According to the latest research,HIIT can reduce the platelet response,mitigate myocardial ischemia-reperfusion injury,and increase the exercise compliance of ACS patients more significantly than MICT.Moreover,it does not increase the risk of thrombotic adverse events or malignant arrhythmia.Therefore,HIIT is expected to become an important part of exercise prescription in out-of-hospital cardiac rehabilitation strategy for the patients with ACS.


Assuntos
Síndrome Coronariana Aguda , Reabilitação Cardíaca , Insuficiência Cardíaca , Treinamento Intervalado de Alta Intensidade , Humanos , Plaquetas
6.
Opt Express ; 31(3): 3536-3548, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785344

RESUMO

An analytical method is proposed in this paper to achieve complete energy conversion in sum frequency generation based on the Lewis-Riesenfeld invariants theory. In the proposed scheme, a quasi-adiabatic single control parameter model is established, and the value of single control parameter is selected to make the initial eigenstate perfectly converted to the final eigenstate as needed. Corresponding to the nonlinear frequency conversion process, a nonlinear crystal structure is designed by inverse engineering using the optimal control theory. It is robust against perturbations of the coupling coefficient and phase mismatch, including variations in the pump intensity and crystal polarization period, and achieves almost 100% conversion efficiency at any crystal length. Theoretical simulations show that frequency conversion can be achieved in the wavelength range of 2.6 µm-3.6 µm, and the spectral bandwidth of conversion efficiency exceeds 50% and approaches 400 nm when the crystal length L = 1 mm.

7.
Angew Chem Int Ed Engl ; 62(11): e202217458, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36640120

RESUMO

Constructing efficient artificial solid electrolyte interface (SEI) film is extremely vital for the practical application of lithium metal batteries. Herein, a dense artificial SEI film, in which lithiophilic Zn/Lix Zny are uniformly but nonconsecutively dispersed in the consecutive Li+ -conductors of Lix SiOy , Li2 O and LiOH, is constructed via the in situ reaction of layered zinc silicate nanosheets and Li. The consecutive Li+ -conductors can promote the desolvation process of solvated-Li+ and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of lithium ions, and lower the nucleation barrier. Therefore, a low polarization of ≈50 mV for 750 h at 2.0 mA cm-2 in symmetric cells, and a high capacity retention of 99.2 % in full cells with a high lithium iron phosphate areal loading of ≈13 mg cm-2 are achieved. This work offers new sights to develop advanced alkali metal anodes for efficient energy storage.

8.
Front Cardiovasc Med ; 9: 943377, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36148074

RESUMO

Background: Sacubitril/valsartan therapy reduced the risks of death and of hospitalization for heart failure (HF). HF and cardiac arrhythmias have shared physiological mechanisems. Therefore, sacubitril/valsartan may exhibit anti-arrhythmic properties in HF. The purpose of this study was to evaluate the effect of sacubitril/valsartan on the occurrence of cardiac arrhythmias and the risk of sudden cardiac death (SCD) in HF. Methods: This meta-analysis was performed according to PRISMA guidelines. We searched PubMed and Embase (from inception up to 6 February 2022) to identify randomized control trials (RCTs) on the effect of sacubitril/valsartan on the occurrence of cardiac arrhythmias and the risk of SCD in HF. Primary outcomes were the occurrence of atrial arrhythmias, ventricular arrhythmias, and SCD. Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled using a random-effects model for meta-analysis. Results: We included 9 RCTs (published between 2012 and 2021) with 18,500 patients (9,244 sacubitril/valsartan vs. 9,256 active control). Enalapril and valsartan were used as active control in six and two studies, respectively. Follow-up ranged from 2 to 35 months. The cumulative occurrence of events was 76, 13, and 48 per 1,000 patient-years for atrial arrhythmias, ventricular arrhythmias and SCD, respectively. There was no significant association between sacubitril/valsartan therapy and the occurrence of atrial arrhythmias (RR 1.06; 95% CI: 0.97-1.17; P = 0.19) and ventricular arrhythmias (RR 0.86; 95% CI 0.68-1.10; P = 0.24). However, sacubitril/valsartan therapy significantly reduced the risk of SCD (RR 0.79; 95% CI 0.70-0.90; P = 0.03) compared with control. Conclusion: No association between sacubitril/valsartan therapy and the occurrence of atrial and ventricular arrhythmias was found, but sacubitril/valsartan therapy significantly reduced the risk of SCD.

9.
Chemistry ; 28(31): e202200363, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35332603

RESUMO

As competitive next-generation rechargeable batteries, lithium-sulfur batteries (LSBs) suffer from the shuttle effect and the sluggish kinetics of intermediate polysulfides during charge and discharge processes, adversely affecting their electrochemical performances and actual applications. Herein, we demonstrate a polymer encapsulation strategy to synthesize atomic Fe and N co-doped hollow carbon nanospheres (Fe-NHC) with Fe-Nx sites for modifying commercial PP separator of LSBs to suppress the shuttle effect and promote the kinetics of intermediate polysulfides. Benefiting from the excellent structural design, the doped-N with positive charges could effectively adsorb negatively charged soluble polysulfides, help attract the soluble polysulfides to the Fe atoms and boost the catalytic transformation of the soluble polysulfides. Additionally, such a thin carbon shell could provide a short mass diffusion pathway and hence promote the adsorption and the catalytic conversion. Therefore, the battery with the Fe-NHC/PP separator delivers outstanding cycling and rate performances. At the large current density of 1 C, the specific capacity is 1079 mA h g-1 and maintains a low loss of 0.076 % per cycle within 500 cycles. Even at a harsh current density of 4 C, a high capacity of 824 mA h g-1 is still achieved, indicating the advantage of the Fe-NHC/PP separator in LSBs.

10.
J Geriatr Cardiol ; 18(10): 796-808, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34754291

RESUMO

BACKGROUND: Increased homocysteine levels are associated with the risk of cardiovascular disease (CVD) and death. However, their prevention has not been effective in decreasing CVD risk. This study investigated the individual and combined associations of hyperhomocysteinemia and hypertension with incident CVD events and all-cause death in the Chinese elderly population without a history of CVD. METHODS: This prospective study was conducted among 1,257 elderly participants (mean age: 69 years). A questionnaire survey, physical examinations, and laboratory tests were conducted to collect baseline data. Hyperhomocysteinemia was defined as homocysteine level ≥ 15 µmol/L. H-type hypertension was defined as concomitant hypertension and hyperhomocysteinemia. Multivariate Cox regression analysis was used to evaluate individual and combined associations of hyperhomocysteinemia and hypertension with the risks of incident CVD events and all-cause death. RESULTS: Over a median of 4.84-year follow-up, hyperhomocysteinemia was independently associated with incident CVD events and all-cause death. The hazard ratios (HRs) were 1.45 (95% CI: 1.01-2.08) for incident CVD events and 1.55 (95% CI: 1.04-2.30) for all-cause death. After adjustment for confounding factors, H-type hypertension had the highest HRs for incident CVD events and all-cause death. The fully adjusted HRs were 2.44 for incident CVD events (95% CI: 1.28-4.65), 2.07 for stroke events (95% CI: 1.01-4.29), 8.33 for coronary events (95% CI: 1.10-63.11), and 2.31 for all-cause death (95% CI: 1.15-4.62). CONCLUSIONS: Hyperhomocysteinemia was an independent risk factor, and when accompanied by hypertension, it contributed to incident CVD events and all-cause death in the Chinese elderly population without a history of CVD.

11.
Small ; 17(38): e2101857, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34350696

RESUMO

Although organosulfur compounds can protect lithium anodes, participate in the redox reaction, and suppress the shuttle effect, the sluggish electrochemical dynamics of their bulk structure and the notorious shuttle effect of covalent long-chain sulfurs largely impede their actual applications. Herein, sulfurized carbon nanotube@aminophenol-formaldehyde (SC@A) with covalently linked short-chain sulfurs is firstly synthesized by in situ polymerization of aminophenol-formaldehyde (AF) on the surface of carbon nanotubes (CNTs) followed by acetone etching and inverse sulfurization processes, forming mesoporous yolk-shell organosulfur nanotubes with abundant internal joints between the yolk of CNTs and the shell of sulfurized AF for the first time. In situ Raman spectra, in situ XRD patterns, and ex situ XPS spectra verify that the covalent short-chain sulfurs bring about a reversible solid-solid conversion process of sulfur, thoroughly avoiding the shuttle effect. The mesoporous yolk-shell structure with abundant internal joints can effectively accommodate the volume change, fully expose active sites and efficiently improve the transport of electrons and lithium ions, thus highly promoting the solid-solid electrochemical reaction kinetics. Therefore, the SC@A cathode exhibits a superior specific capacity of 841 mAh g-1 and a capacity decay of 0.06% per cycle within 500 cycles at a large current density of 5.0 C.

13.
PLoS One ; 16(6): e0253709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34166470

RESUMO

BACKGROUND: The safety of discontinuing oral anticoagulant (OAC) therapy after atrial fibrillation (AF) ablation remains controversial. A meta-analysis was performed to assess the safety and feasibility of discontinuing OAC therapy after successful AF ablation. METHODS: PubMed and Embase were searched up to October 2020 for prospective cohort studies that reported the risk of thromboembolism (TE) after successful AF ablation in off-OAC and on-OAC groups. The primary outcome was the incidence of TE events. The Mantel-Haenszel method with random-effects modeling was used to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: A total of 11,148 patients (7,160 in the off-OAC group and 3,988 in the on-OAC group) from 10 studies were included to meta-analysis. No significant difference in TE between both groups was observed (OR, 0.73; 95%CI, 0.51-1.05; I2 = 0.0%). The risk of major bleeding in off-OAC group was significantly lower compared to the on-OAC group (OR, 0.18; 95%CI, 0.07-0.51; I2 = 51.7%). CONCLUSIONS: Our study suggests that it may be safe to discontinue OAC therapy in patients after successful AF ablation. Additionally, an increased risk of major bleeding was observed in patients on OAC. However, the results of this meta-analysis should be interpreted with caution because of the heterogeneity among the included study designs. Large-scale and adequately powered randomized controlled trials are warranted to confirm these findings.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/terapia , Ablação por Cateter , Administração Oral , Fibrilação Atrial/epidemiologia , Humanos , Incidência , Estudos Prospectivos
16.
World J Clin Cases ; 8(20): 4700-4707, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33195637

RESUMO

BACKGROUND: Chronic pulmonary aspergillosis (CPA) is a rare syndrome that is often accompanied by gradual lung tissue destruction. Voriconazole is usually employed as the first-line agent for CPA treatment. However, some patients can develop hepatotoxicity and often were forced to stop voriconazole treatment. AIM: To record the improving trend of liver function and the therapeutic effects in patients after lowering the trough concentration of voriconazole. METHODS: This study retrospectively analyzed 12 adult CPA patients who developed hepatotoxicity during the voriconazole treatment. In these patients, the oral dose was reduced to 3/4 or 1/2 of the standard dose (4 mg/kg, twice daily), and the lower limit of voriconazole trough concentration was maintained more than 0.5 µg/mL. The trend of remission of liver toxicity after drug reduction in 12 patients was recorded. During the same period, 25 patients who received standard doses served as the control group. Data from the two groups were collected and analyzed for different parameters such as demographic characteristics, underlying pulmonary disorders, laboratory tests, and therapeutic effect. The differences between the two groups were statistically compared. RESULTS: Hepatotoxicity occurred in 12 patients within 28-65 d after oral voriconazole treatment. Hepatotoxicity was mainly manifested by the significantly increased level of gamma-glutamyltransferase and a slight increase of alanine aminotransferase and aspartate aminotransferase. The oral dose of voriconazole was reduced to approximately 3 mg/kg in seven patients and approximately 2 mg/kg in five patients. The average trough concentrations for the 12 patients before and after voriconazole oral dose reduction were 3.17 ± 1.47 µg/mL (1.5-6.0 µg/mL) and 1.70 ± 0.78 µg/mL (0.6-3.3 µg/mL), respectively (P = 0.02). After lowering the trough concentrations, the hepatotoxicity was alleviated in all the patients. However, gamma-glutamyltransferase levels declined slowly. After 4 mo of treatment, 7 of the 12 patients were successfully treated in the low trough concentrations group (41.7%). Similarly, 8 of the 25 patients in the standard treatment dose group (32.0%) were effectively treated. There was no statistical difference between the groups (P = 0.72). CONCLUSION: Reducing the lower limit of the voriconazole trough concentration to 0.5 µg/mL can alleviate the hepatotoxicity and maintained certain clinical efficacy in CPA patients; however, patients should be closely monitored.

17.
Neurosci Lett ; 730: 135034, 2020 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-32404250

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative diseases. Identifying PD cognitive impairment (PDCI) in the early stage will help slow or prevent PD dementia. Susceptibility loci for PDCI are inconsistent in different studies. The aim of this study is to determine susceptibility loci for PDCI in the Han Chinese population. A total of 24 single nucleotide polymorphisms (SNPs) associated with PDCI were genotyped by Massarray system and Sanger sequencing in 158 PD patients and 275 healthy controls. Two SNPs (rs34778348 in LRRK2, rs78973108 in GBA) had different genotype distribution between PD and controls. None of risk SNPs was identified between PDCI and PD with normal cognition (PDNC). Aging and high Unified Parkinson's Disease Rating Scale (UPDRS) score were the independent risk factors for PDCI, rather than sex and SNPs. Our study showed that none of risk SNPs was identified to be significantly associated with cognitive decline of PD patients, indicating the effect of susceptibility loci on PDCI is subtle in the Han Chinese population.


Assuntos
Disfunção Cognitiva/genética , Predisposição Genética para Doença/genética , Doença de Parkinson/genética , Doença de Parkinson/fisiopatologia , Idoso , Doença de Alzheimer/genética , Povo Asiático/genética , Cognição/fisiologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/fisiopatologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
18.
Eur J Radiol ; 126: 108905, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32145596

RESUMO

PURPOSE: To analyze the imaging manifestations of mediastinal hemangioma (MH) by CT and MRI to aid in its successful diagnosis and preoperative evaluation. METHODS: Seventeen cases of MH diagnosed by histopathology combined with CT and MRI were retrospectively collected; and their CT and MRI features, including the lesions' site and range, shape, size, margin, density or signal, enhancement pattern, mass-cardiovascular interface, mass-pulmonary interface, and other characteristics were evaluated. RESULTS: The anterior, middle, and posterior mediastinum were involved in 13, 13, and 8 cases, respectively. The masses size varied from 20 to 233 mm. Irregular, dumbbell-like, and oval masses were found in 13, 2, and 2 cases, respectively, while with pampiniform growth in 16 cases and expansive growth in 1 case. Mixed density, homogeneous density solid masses, and heterogeneous density masses with dominant fat were found in 9, 5, and 3 cases, respectively, showing mild or significant enhancement in aortic phase while no or mild enhancement in pulmonary artery phase. Draining veins were found in 16 cases and feeding arteries in 10 cases. Phleboliths were detected in 10 cases, splenic hemangiomas in 6 cases, and left lateral-chest-wall hemangioma in 1 case. In MRI sequences, mixed signal was found on T1WI and heterogeneous hypersignal with nodular or linear hyposignal on T2WI in 5 cases, mild or significant enhancement in 4 cases, draining veins in 2 cases, and no feeding arteries or phleboliths were seen. CONCLUSION: Presence of phleboliths, pampiniform growth pattern, and aberrant draining veins are relatively specific characteristics in diagnosing MH.


Assuntos
Hemangioma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neoplasias do Mediastino/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Criança , Feminino , Hemangioma/patologia , Humanos , Masculino , Neoplasias do Mediastino/patologia , Mediastino/diagnóstico por imagem , Mediastino/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
19.
ACS Appl Mater Interfaces ; 12(12): 14037-14048, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32129062

RESUMO

To develop ternary transition-metal germanate anodes with superior lithium storage performances for lithium-ion batteries, a novel capacity counterbalance approach in one compound is designed by introducing an electrocatalytic conversion-type component with a positive cycling trend to compensate the negative cycling trend of the GeO2 component. Novel cobalt germanate hydroxide (CGH) nanoplates chemically bonded on reduced graphene oxide (RGO) sheets are thus synthesized with a mild one-pot hydrothermal approach, constructing maximal face-to-face contact interfaces with interfacial bonds to boost the electrochemical conversion reactions. Furthermore, the hydroxyl groups (Co-OH) of CGH nanoplates are regulated by thermal annealing treatments, thus controlling the capacity contribution resulting from the electrocatalytic conversion reaction of LiOH to exactly offset the capacity fading of GeO2. The results on the CGH electrodes at different cycling potentials confirm the stepwise electrochemical reactions of Co, GeO2, and LiOH. The equilibrium of these electrochemical reactions ensures a stable cycling capacity without obvious fluctuations. Consequently, the optimal CGH/RGO hybrid anode delivers a reversible capacity as high as 1136 mA h g-1 at 0.1 A g-1 until 100 cycles. It also exhibits a long cyclability with a retained capacity of 560 mA h g-1 at 1 A g-1 until 1000 cycles. This work demonstrates a general and efficient capacity counterbalance method to highly boost lithium storage performances in terms of high capacity and long-term cyclability.

20.
ACS Appl Mater Interfaces ; 11(36): 33091-33101, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31414794

RESUMO

Transition metal carbonates/hydroxides have attracted much attention as appealing anode materials due to their considerable reversible electrochemical catalytic conversion capacity. However, their serious positive or negative trends with cycles caused by the electrochemical catalytic conversion seriously affect their practical applications. Herein, novel one-dimensional cobalt hydroxide carbonate (CHC) nanomaterials are tightly anchored on reduced graphene oxide (RGO) sheets via a facile one-pot hydrothermal synthesis, forming surface-confined domains to further restrict the electrochemical catalytic conversion process. The analysis on the cycled electrodes at varied potentials confirms that the added capacity of CHC arises from the step-by-step reversible reactions of Li2CO3 and LiOH under the electrochemical catalysis of Co metal generated by the conversion reaction of CHC. The reversible reaction of Li2CO3 is followed closely by that of LiOH in the discharge process, while the order is opposite in the charge process. Such a step-by-step electrochemical catalytic conversion process could confine each other to accommodate the volume change and avoid side reactions. The confined effect is further enhanced by limiting the width and length of the CHC, which are determined by regulating the nucleation and growth of CHC on the surface of RGO, leading to an extraordinary cyclability. The optimized CHC/RGO hybrid maintains a high reversible capacity of 1110 mA h g-1 after 100 cycles at 0.1 A g-1, which is much higher than the theoretical value of CHC (506 mA h g-1) on the basis of the recognized conversion reaction. Furthermore, it keeps high reversible capacities of 755 and 506 mA h g-1 after 200 cycles at 1 and 2 A g-1, respectively, exhibiting a high-rate cyclability with the lowest coefficient of variance of 9.4% among the reported ones. The confined step-by-step electrochemical catalytic conversion process facilitates high lithium storage capacity and satisfactory cyclability with a pretty low variance coefficient.

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