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1.
Small ; : e2403435, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38874079

ABSTRACT

The cycling lifespan of Li-metal batteries is compromised by the unstable solid electrolyte interphase (SEI) and the continuous Li dendrites, restricting their practical implementations. Given these challenges, establishing an artificial SEI holds promise. Herein, a trinitarian gradient interphase is innovatively designed through composite coatings of magnesium fluoride (MgF2), N-hexadecyltrimethylammonium chloride (CTAC), and polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP) on Li-metal anode (LMA). Specifically, the MgF2/CTAC/PVDF-HFP SEI spontaneously forms a lithium fluoride (LiF)-rich PVDF-HFP-based SEI, along with lithium-magnesium (Li-Mg) alloy substrate as lithiophilic electronic conductor and positively charged CTAC during plating. Noticeably, the Li-Mg alloy homogenizes the distribution of electric field and reduce the internal resistance, while the electronically insulated LiF/PVDF-HFP composite SEI offers fast ion-conducting and mechanical flexibility, accommodating the volumetric expansion and ensuring stable Li-ion flux. Additionally, CTAC at the dendritic tip is pivotal for mitigating dendrites through its electrostatic shield mechanism. Innovatively, this trinitarian synergistic mechanism, which facilitates colossal granular Li deposits, constructs a dendrite-free LMA, leading to stable cycling performances in practical Li||LFP, popular Li||NCM811, and promising Li||S full cells. This work demonstrates the design of multifunctional composite SEI for comprehensive Li protection, thereby inspiring further advancements in artificial SEI engineering for alkali-metal batteries.

3.
PLoS One ; 16(9): e0253394, 2021.
Article in English | MEDLINE | ID: mdl-34506485

ABSTRACT

Long project cycle and uncertainties are important characteristics of public-private partnership (PPP) projects. Since the introduction of PPP projects in China, the timing of capital withdrawal has become important. With the emergence of risk factors during the course of the project, it will face the problem of investment withdrawal by social capital financial investors. Escalation of commitment (EOC) refers to the erroneous behaviour of project decision makers who do not promptly withdraw from a project when they receive negative feedback and continue to invest resources in the project. EOC not only causes more unnecessary losses but also adversely affects decision makers. Therefore, it is crucial to clarify the impact of EOC on the choice of the exit timing of social capital. This article adopts literature survey method and quantitative analysis method: introducing the theory of maximization of income into the real option model, combining the net present value method with the binary tree option pricing model, constructing the decision-making model to analyze the exit timing of PPP social capital in the context of EOC. Then combined numerical simulation and empirical analysis to verify the effectiveness of the decision-making model, discussed the reasons why the social capital party chooses EOC, and proposes measures for controlling EOC. The higher the degree of completion of the project, the easier it is for the person in charge of the project to make inaccurate judgements about the project due to personal psychological factors, and the easier it is for EOC to occur. Therefore, after setting the minimum goal of the project, the decision maker needs to accurately evaluate the existing value of the project to avoid falling into decision-making errors.


Subject(s)
Investments/economics , Public-Private Sector Partnerships/economics , China , Decision Making , Humans , Models, Economic
4.
Zhongguo Zhong Yao Za Zhi ; 46(8): 2079-2083, 2021 Apr.
Article in Chinese | MEDLINE | ID: mdl-33982523

ABSTRACT

Nine secondary metabolites(S)-5-hydroxy-4-methylchroman-2-one(1), 4-methoxynaphthalene-1,5-diol(2), 8-methoxynaphthalene-1,7-diol(3), 1,8-dimethoxynaphthalene(4),(2R,4S)-2,3-dihydro-2-methyl-benzopyran-4,5-diol(5),(2R,4R)-3,4-dihydro-4-methoxy-2-methyl-2H-1-benzopyran-5-ol(6), 7-O-α-D-ribosyl-2,3-dihydro-5-hydroxy-2-methyl-chromen-4-one(7),(R)-3-methoxyl-1-(2,6-dihydroxyphenyl)-butan-1-one(8) and helicascolide A(9) were isolated from endophytic fungus Cladosporium sp. JJM22 by using column chromatographies of silica gel and ODS, and semi-preparative HPLC. Their structures were analyzed on the basis of spectroscopic and chemical data, especially NMR and MS. All isolated compounds were evaluated for their anti-inflammatory activities by examining the inhibitory activities on nitric oxide(NO) production induced by lipopolysaccharide in mouse macrophage RAW264.7 cells in vitro. Compounds 2-4 showed inhibitory activities.


Subject(s)
Rhizophoraceae , Animals , Benzopyrans , Cladosporium , Fungi , Mice , Molecular Structure
5.
J Clin Endocrinol Metab ; 106(3): e1221-e1230, 2021 03 08.
Article in English | MEDLINE | ID: mdl-33274355

ABSTRACT

CONTEXT: Thyroid hormones play an important role in metabolic homeostasis, and higher levels have been associated with cardiometabolic risk. OBJECTIVE: To examine the association of cardiometabolic risk factors with TSH levels in US youth. METHODS: Cross-sectional study of youth aged 12 to 18 years without known thyroid abnormalities from 5 National Health and Nutrition Examination Survey cycles (n = 2818) representing 15.4 million US children. Subclinical hypothyroidism (SH) was defined as thyrotropin (TSH) levels of 4.5 to 10 mIU/L. Assessed cardiometabolic risk factors include abdominal obesity (waist circumference >90th percentile), hypertriglyceridemia (triglyceride ≥130 mg/dL), low high-density lipoprotein cholesterol (<40 mg/dL), elevated blood pressure (systolic and diastolic blood pressure ≥90th percentile), hyperglycemia (fasting blood glucose ≥100 mg/dL, or known diabetes), insulin resistance (homeostatic model for insulin resistance > 3.16), and elevated alanine transferase (≥ 50 for boys and ≥44 U/L for girls). Age and sex- specific percentiles for thyroid parameters were calculated. RESULTS: In this cohort of youth (51.3% male), 31.2% had overweight/obesity. The prevalence of SH was 2.0% (95% CI 1.2-3.1). The median TSH levels were higher in youth with overweight/obesity (P < 0.001). Adjusting for age, sex, race/ethnicity, and obesity, youth with TSH in the fourth quantile had higher odds of abdominal obesity (OR 2.53 [1.43-4.46], P = .002), insulin resistance (OR 2.82 [1.42-5.57], P = .003), and ≥2 cardiometabolic risk factors (CMRF) (OR 2.20 [1.23-3.95], P = .009). CONCLUSION: The prevalence of SH is low in US youth. The higher odds of insulin resistance and cardiometabolic risk factors in youth with TSH levels >75th percentile requires further study.


Subject(s)
Cardiometabolic Risk Factors , Thyroid Gland/physiology , Thyrotropin/blood , Adolescent , Adolescent Health , Child , Cohort Studies , Cross-Sectional Studies , Female , Humans , Male , Nutrition Surveys , Reference Values , Thyroid Diseases/blood , Thyroid Diseases/epidemiology , Thyroid Diseases/physiopathology , Thyroid Function Tests/standards , United States/epidemiology
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