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1.
ACS Nano ; 17(10): 8980-8991, 2023 May 23.
Article in English | MEDLINE | ID: mdl-37155575

ABSTRACT

Rechargeable magnesium (Mg) batteries can offer higher volumetric energy densities and be safer than their conventional counterparts, lithium-ion batteries. However, their practical implementation is impeded due to the passivation of the Mg metal anode or the severe corrosion of the cell parts in conventional electrolyte systems. Here, we present a chemical activation strategy to facilitate the Mg deposition/stripping process in additive-free simple salt electrolytes. By exploiting the simple immersion-triggered spontaneous chemical reaction between reactive organic halides and Mg metal, the activated Mg anode exhibited an overpotential below 0.2 V and a Coulombic efficiency as high as 99.5% in a Mg(TFSI)2 electrolyte. Comprehensive analyses reveal simultaneous evolution of morphology and interphasial chemistry during the activation process, through which stable Mg cycling over 990 cycles was attained. Our activation strategy enabled the efficient cycling of Mg full-cell candidates using commercially available electrolytes, thereby offering possibilities of building practical Mg batteries.

2.
J Am Chem Soc ; 143(24): 9169-9176, 2021 Jun 23.
Article in English | MEDLINE | ID: mdl-34111352

ABSTRACT

Although often overlooked in anode research, the anode's initial Coulombic efficiency (ICE) is a crucial factor dictating the energy density of a practical Li-ion battery. For next-generation anodes, a blend of graphite and Si/SiOx represents the most practical way to balance capacity and cycle life, but its low ICE limits its commercial viability. Here, we develop a chemical prelithiation method to maximize the ICE of the blend anodes using a reductive Li-arene complex solution of regulated solvation power, which enables a full cell to exhibit a near-ideal energy density. To prevent structural degradation of the blend during prelithiation, we investigate a solvation rule to direct the Li+ intercalation mechanism. Combined spectroscopy and density functional theory calculations reveal that in weakly solvating solutions, where the Li+-anion interaction is enhanced, free solvated-ion formation is inhibited during Li+ desolvation, thereby mitigating solvated-ion intercalation into graphite and allowing stable prelithiation of the blend. Given the ideal ICE of the prelithiated blend anode, a full cell exhibits an energy density of 506 Wh kg-1 (98.6% of the ideal value), with a capacity retention after 250 cycles of 87.3%. This work highlights the promise of adopting chemical prelithiation for high-capacity anodes to achieve practical high-energy batteries.

3.
Angew Chem Int Ed Engl ; 59(34): 14473-14480, 2020 Aug 17.
Article in English | MEDLINE | ID: mdl-32400120

ABSTRACT

Prelithiation is of great interest to Li-ion battery manufacturers as a strategy for compensating for the loss of active Li during initial cycling of a battery, which would otherwise degrade its available energy density. Solution-based chemical prelithiation using a reductive chemical promises unparalleled reaction homogeneity and simplicity. However, the chemicals applied so far cannot dope active Li in Si-based high-capacity anodes but merely form solid-electrolyte interphases, leading to only partial mitigation of the cycle irreversibility. Herein, we show that a molecularly engineered Li-arene complex with a sufficiently low redox potential drives active Li accommodation in Si-based anodes to provide an ideal Li content in a full cell. Fine control over the prelithiation degree and spatial uniformity of active Li throughout the electrodes are achieved by managing time and temperature during immersion, promising both fidelity and low cost of the process for large-scale integration.

4.
Korean J Intern Med ; 35(3): 641-651, 2020 05.
Article in English | MEDLINE | ID: mdl-32392663

ABSTRACT

BACKGROUND/AIMS: We aimed to evaluate site-specific cancer risk in diabetic patients and to investigate causal and temporal relationships by analyzing organ-specific cancer risk according to the duration of diabetes. METHODS: Using a database provided by the Korean National Health Insurance Service, we conducted a retrospective, population-based cohort study of adults aged ≥ 30 years from January 2005 to December 2013. To verify the possibility of detection bias or reverse causation, we compared hazard ratios (HRs) for each cancer according to the following duration of diabetes: less than 6 months, 6 months to 3 years, and more than 3 years. RESULTS: The incidence of overall cancer per 1,000 person-years was higher in patients with diabetes than in those without diabetes (20.36 vs. 10.83). The overall cancer risk according to the duration of diabetes was the highest within the first 6 months after diagnosis (HR, 2.03; 95% confidence interval [CI], 1.99 to 2.07), and the HR decreased with the duration of diabetes, ranging from 1.19 (95% CI, 1.18 to 1.21) between 6 months and 3 years to 1.12 (95% CI, 1.11 to 1.13) after 3 years. Both overall cancer risk and HR remained significantly higher in patients with diabetes than in those without diabetes. The risk for prostate cancer was higher in men with diabetes than in those without diabetes (HR, 1.12; 95% CI, 1.10 to 1.14). In women, the risk for endometrial cancer was significantly higher in patients with diabetes than in those without diabetes throughout the duration of diabetes. CONCLUSION: The risk for stomach, colorectum, liver, pancreas, and kidney cancer appeared to be higher in patients with diabetes than in those without diabetes regardless of the sex or duration of diabetes.


Subject(s)
Diabetes Mellitus, Type 2 , Neoplasms , Adult , Cohort Studies , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/epidemiology , Female , Humans , Incidence , Male , Neoplasms/diagnosis , Neoplasms/epidemiology , Republic of Korea/epidemiology , Retrospective Studies , Risk Factors
5.
Cyberpsychol Behav Soc Netw ; 18(4): 221-7, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25803204

ABSTRACT

Previous studies have revealed that information and communication technologies (ICTs) play a crucial role in parenting. Utilizing a national sample of mothers, the current study addresses mothers' information-seeking behaviors using ICTs utilizing the sense-making theoretical approach. Specifically, the study explored mothers' gap-bridging activities via online information venues including blogs, discussion boards/chatrooms, e-mailed newsletters, and online courses. Further, the associations were examined between mothers' demographic characteristics and their patterns of gap-bridging activities using online information venues. Latent class analysis revealed five latent classes: limited gap bridging, active gap bridging, problem identifiers, perspective explorers, and reassurance seekers. The "limited gap bridging" latent class was the most common class across online information venues. The other latent classes illustrate a more complex picture of mothers' gap-bridging activities depending on their needs. Mothers' demographic characteristics were associated with their patterns of gap-bridging activities. Implications of these findings for future research are discussed.


Subject(s)
Information Seeking Behavior , Internet/statistics & numerical data , Mothers , Parenting , Adult , Communication , Electronic Mail , Female , Humans , Social Networking
6.
J Marital Fam Ther ; 39(4): 515-29, 2013 Oct.
Article in English | MEDLINE | ID: mdl-25800426

ABSTRACT

Study purpose was to investigate adapted social support instruments of nurturance and affiliation with male and female entrepreneurs and spouses starting a new business. Family Fundamental Interpersonal Relationship Orientation theory was the theoretical grounding. Business structure differed by entrepreneur gender in both direct and indirect spousal involvement. Both couple types were highly connected with their firms having high nurturance and affiliation scores. When couple discrepancies were compared, more male entrepreneur couples had shared meaning on business-oriented nurturance questions compared with female entrepreneur couples. The opposite was true for shared meaning on relationship-oriented nurturance. For all affiliation questions, more male entrepreneur couples had shared meaning than did female entrepreneur couples. Clinical applications of resulting instruments are discussed.


Subject(s)
Commerce , Marriage/psychology , Social Support , Adult , Female , Humans , Male , Psychological Tests , Sex Factors , Surveys and Questionnaires
7.
J Korean Med Sci ; 20(6): 1066-9, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16361824

ABSTRACT

Most of the interstitial lung diseases are rare, chronic, progressive and fatal disorders, especially in familial form. The etiology of the majority of interstitial lung disease is still unknown. Host susceptibility, genetic and environmental factors may influence clinical expression of each disease. With familial interstitial lung diseases, mutations of surfactant protein B and surfactant protein C or other additional genetic mechanisms (e.g. mutation of the gene for ATP-binding cassette transporter A3) could be associated. We found a 21 month-old girl with respiratory symptoms, abnormal radiographic findings and abnormal open lung biopsy findings compatible with nonspecific interstitial pneumonitis that is similar to those of her older sister died from this disease. We performed genetic studies of the patient and her parents, but we could not find any mutation in our case. High-dose intravenous methylprednisolone and oral hydroxychloroquine were administered and she is still alive without progression during 21 months of follow-up.


Subject(s)
Lung Diseases, Interstitial/genetics , Child, Preschool , Female , Humans , Hydroxychloroquine/administration & dosage , Infant , Korea , Lung Diseases, Interstitial/drug therapy , Lung Diseases, Interstitial/pathology , Lung Diseases, Interstitial/physiopathology , Methylprednisolone/administration & dosage , Siblings , Tomography, X-Ray Computed
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