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1.
J Am Chem Soc ; 146(7): 4327-4332, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38277433

RESUMEN

The structural exploration of three-dimensional covalent organic frameworks (3D COFs) is of great significance to the development of COF materials. Different from structurally diverse MOFs, which have a variety of connectivity (3-24), now the valency of 3D COFs is limited to only 4, 6, and 8. Therefore, the exploration of organic building blocks with higher connectivity is a necessary path to broaden the scope of 3D COF structures. Herein, for the first time, we have designed and synthesized a 12-connected triptycene-based precursor (triptycene-12-CHO) with 12 symmetrical distributions of aldehyde groups, which is also the highest valency reported until now. Based on this unique 12-connected structure, we have successfully prepared a novel 3D COF with lnj topology (termed 3D-lnj-COF). The as-synthesized 3D COF exhibits honeycomb main pores and permanent porosity with a Brunauer-Emmett-Teller surface area of 1159.6 m2 g-1. This work not only provides a strategy for synthesizing precursors with a high connectivity but also provides inspiration for enriching the variety of 3D COFs.

2.
J Am Chem Soc ; 143(1): 92-96, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33332116

RESUMEN

Three-dimensional covalent organic frameworks (3D-COFs) are emerging as designable porous materials because of their unique structural characteristics and porous features. However, because of the lack of 3D organic building units and the less reversible covalent bonds, the topologies of 3D-COFs to date have been limited to dia, ctn, ffc, bor, rra, srs, pts, lon, stp, acs, tbo, bcu, and fjh. Here we report a 3D-COF with the ceq topology utilizing a D3h-symmetric triangular prism vertex with a planar triangular linker. The as-synthesized COF displays a twofold-interpenetrated structure with a Brunauer-Emmett-Teller surface area of 1148.6 m2 g-1. Gas sorption measurements revealed that 3D-ceq-COF could efficiently absorb CO2, CH4, and H2 under a moderate surface area. This work provides new building units and approaches for structural and application exploration of 3D-COFs.

3.
J Am Chem Soc ; 139(49): 17771-17774, 2017 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-29179538

RESUMEN

Covalent organic frameworks (COFs) have emerged as functional materials for various potential applications. However, the availability of three-dimensional (3D) COFs is still limited, and nearly all of them exhibit neutral porous skeletons. Here we report a general strategy to design porous positively charged 3D ionic COFs by incorporation of cationic monomers in the framework. The obtained 3D COFs are built of 3-fold interpenetrated diamond net and show impressive surface area and CO2 uptakes. The ion-exchange ability of 3D ionic COFs has been highlighted by reversible removal of nuclear waste model ions and excellent size-selective capture for anionic pollutants. This research thereby provides a new perspective to explore 3D COFs as a versatile type of ion-exchange materials.

4.
J Pers Assess ; 98(3): 310-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26421444

RESUMEN

The Circumplex Scales of Interpersonal Values (CSIV) is a 64-item self-report measure of goals from each octant of the interpersonal circumplex. We used item response theory methods to compare whether dominance models or ideal point models best described how people respond to CSIV items. Specifically, we fit a polytomous dominance model called the generalized partial credit model and an ideal point model of similar complexity called the generalized graded unfolding model to the responses of 1,893 college students. The results of both graphical comparisons of item characteristic curves and statistical comparisons of model fit suggested that an ideal point model best describes the process of responding to CSIV items. The different models produced different rank orderings of high-scoring respondents, but overall the models did not differ in their prediction of criterion variables (agentic and communal interpersonal traits and implicit motives).


Asunto(s)
Relaciones Interpersonales , Modelos Psicológicos , Psicometría/métodos , Valores Sociales , Humanos , Determinación de la Personalidad , Reproducibilidad de los Resultados
5.
J Orthop Res ; 42(3): 661-670, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37804208

RESUMEN

The objective of this study was to measure how much of the superolateral femoral neck should be removed to reduce the incidence of wedge effect. Simulating surgery: Computed Tomography images of 131 intertrochanteric fracture patients were included, three-dimensionally reconstructed, virtually reduced and implanted with Proximal Femoral Nail Antirotation blade-Ⅱ(PFNA-Ⅱ) nail. The antero-posterior length and media-lateral width of the intersection between superolateral femoral neck and PFNA-Ⅱ nail were measured. Retrospective study: The pre- and postoperative CT of 30 patients were collected. The average varus angle of the neck-shaft angle and the correlation between the angles and the difference in the actual and estimated width of the fragments removed were measured. Models of 108 patient were selected for analysis. The average antero-posterior length and media-lateral width were 14.46 mm (14.00-14.93 mm) and 9.33 mm (8.79-9.87 mm), respectively. The AO/OTA classification was not significantly associated with the outcome, but the gender was. In the retrospective study, the mean value of the varus angles was -4.58° (SE = 6.85°), and the difference of width was strongly positively correlated with the varus angle with a correlation coefficient of 0.698. Results obtained in this study can improve the understanding of this region and help surgeons to make appropriate preoperative planning to reduce the incidence of wedge effect. Retrospective study provided effective proof of the reliability of this study.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas de Cadera , Humanos , Cuello Femoral/diagnóstico por imagen , Cuello Femoral/cirugía , Estudios Retrospectivos , Fijación Intramedular de Fracturas/métodos , Reproducibilidad de los Resultados , Clavos Ortopédicos , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/cirugía , Resultado del Tratamiento
6.
Environ Sci Pollut Res Int ; 30(17): 50309-50318, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36790707

RESUMEN

This investigation attempts to look at how digital finance and environmental taxes affect environmental entrepreneurship. We have used the QARDL model to evaluate the short- and long-run estimations. The main findings of the QARDL model confirm that digital finance is vital in promoting the environmental entrepreneurship model in the long run. In contrast, in the short run, digital finance does not significantly impact environmental entrepreneurship. Moreover, environment-related taxes, environmental innovations, and economic development promote environmental entrepreneurship in the long run across most quantiles. However, in the short run, environment-related taxes and economic development do not exert any significant impact on environmental entrepreneurship in almost all quantiles, while environmental innovation promotes environmental entrepreneurship in most quantiles. Further, asymmetric effects of digital finance (ATM and debit card), environment-related taxes, environmental innovations, and economic development are confirmed in the long run; in the short run, asymmetric effects are observed in the case of environmental innovation in both the models. Following the results, we suggest that the public and private sectors should do more financing to promote ecopreneurship in society. Moreover, more taxes should be imposed on entrepreneurs who do not adopt green practices.


Asunto(s)
Emprendimiento , Sector Privado , China , Desarrollo Económico , Impuestos
7.
Nat Commun ; 13(1): 172, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013293

RESUMEN

Lithium reactivity with electrolytes leads to their continuous consumption and dendrite growth, which constitute major obstacles to harnessing the tremendous energy of lithium-metal anode in a reversible manner. Considerable attention has been focused on inhibiting dendrite via interface and electrolyte engineering, while admitting electrolyte-lithium metal reactivity as a thermodynamic inevitability. Here, we report the effective suppression of such reactivity through a nano-porous separator. Calculation assisted by diversified characterizations reveals that the separator partially desolvates Li+ in confinement created by its uniform nanopores, and deactivates solvents for electrochemical reduction before Li0-deposition occurs. The consequence of such deactivation is realizing dendrite-free lithium-metal electrode, which even retaining its metallic lustre after long-term cycling in both Li-symmetric cell and high-voltage Li-metal battery with LiNi0.6Mn0.2Co0.2O2 as cathode. The discovery that a nano-structured separator alters both bulk and interfacial behaviors of electrolytes points us toward a new direction to harness lithium-metal as the most promising anode.

8.
Nat Commun ; 13(1): 845, 2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35149679

RESUMEN

Rhenium(I)-carbonyl-diimine complexes have emerged as promising photocatalysts for carbon dioxide reduction with covalent organic frameworks recognized as perfect sensitizers and scaffold support. Such Re complexes/covalent organic frameworks hybrid catalysts have demonstrated high carbon dioxide reduction activities but with strong excitation energy-dependence. In this paper, we rationalize this behavior by the excitation energy-dependent pathways of internal photo-induced charge transfer studied via transient optical spectroscopies and time-dependent density-functional theory calculation. Under band-edge excitation, the excited electrons are quickly injected from covalent organic frameworks moiety into catalytic RheniumI center within picosecond but followed by fast backward geminate recombination. While under excitation with high-energy photon, the injected electrons are located at high-energy levels in RheniumI centers with longer lifetime. Besides those injected electrons to RheniumI center, there still remain some long-lived electrons in covalent organic frameworks moiety which is transferred back from RheniumI. This facilitates the two-electron reaction of carbon dioxide conversion to carbon monoxide.

9.
Arch Gerontol Geriatr ; 95: 104381, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33657489

RESUMEN

BACKGROUND: With the increase in the aging population worldwide, cognitive decline has become an important research topic. The purpose of this study is to examine the cognitive development trajectories and influencing factors of different latent classes of Chinese elderly people. This will provide us with effective guidance for prevention and intervention. METHODS: Four waves of data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) were collected and included 2440 Chinese elderly individuals. The cognitive function of elderly individuals was measured using the Mini Mental State Examination (MMSE). A nonnormal Growth Mixture model (GMM) with five time-invariant covariates was used to identify the different trajectories of cognitive decline in elderly individuals. RESULTS: Three latent decline trajectory groups were identified: stable cognitive group (SCG), high initial level - cognitive decline group (HIL-CDG), and high initial level - cognitive decline group (LIL-CDG). Elderly women were more likely to be assigned to a lower level subgroup than men. People who smoked and played cards or mahjong were more likely to be assigned to a cognitively stable group. CONCLUSION: Education may help raise the upper limit of cognition. Smoking may impair cognitive upper limit. A small amount of alcohol intake and participation in cognitive and physical activities may help the elderly to delay cognitive decline in their later years.


Asunto(s)
Disfunción Cognitiva , Anciano , China , Cognición , Femenino , Humanos , Longevidad , Estudios Longitudinales , Masculino , Pruebas de Estado Mental y Demencia
10.
Front Psychol ; 11: 561358, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33335495

RESUMEN

Emotion regulation (ER) plays a vital role in individuals' well-being and successful functioning. In this study, we attempted to develop a computerized adaptive testing (CAT) to efficiently evaluate ER, namely the CAT-ER. The initial CAT-ER item bank comprised 154 items from six commonly used ER scales, which were completed by 887 participants recruited in China. We conducted unidimensionality testing, item response theory (IRT) model comparison and selection, and IRT item analysis including local independence, item fit, differential item functioning, and item discrimination. Sixty-three items with good psychometric properties were retained in the final CAT-ER. Then, two CAT simulation studies were implemented to assess the CAT-ER, which revealed that the CAT-ER developed in this study performed reasonably well, considering that it greatly lessened the test items and time without losing measurement accuracy.

12.
Artículo en Inglés | MEDLINE | ID: mdl-26335062

RESUMEN

Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS) and density functional theory (DFT) simulations were employed to study 5-amino-2-mercaptobenzimidazole (5-A-2MBI) molecules. Ag colloids were used as SERS substrates which were prepared by using hydroxylamine hydrochloride as reducing agent. Raman vibration modes and SERS characteristic peaks of 5-A-2MBI were assigned with the aid of DFT calculations. The molecular electrostatic potential (MEP) of 5-A-2MBI was used to discuss the possible adsorption behavior of 5-A-2MBI on Ag colloids. The spectral analysis showed that 5-A-2MBI molecules were slightly titled via the sulfur atoms adhering to the surfaces of Ag substrates. The obtained SERS spectral intensity decreased when lowering the 5-A-2MBI concentrations. A final detection limit on the concentration of 5×10(-7) mol · L(-1) was gained. SERS proved to be a simple, fast and reliable method for the detection and characterization of 5-A-2MBI molecules.


Asunto(s)
Bencimidazoles/química , Modelos Moleculares , Teoría Cuántica , Espectrometría Raman , Adsorción , Coloides , Conformación Molecular , Plata/química , Soluciones , Espectrofotometría Ultravioleta , Electricidad Estática , Factores de Tiempo
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