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1.
Inorg Chem ; 63(23): 10756-10766, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38812065

RESUMO

The lead-free halide perovskites possess nontoxicity and excellent chemical stability, whereas relatively weak luminescence intensity limits their potential in practical applications. Therefore, strengthening the luminescence intensity and expanding application fields are urgent tasks for the development of lead-free halide perovskites. In this paper, antimony-doped Cs2NaScCl6 crystals synthesized by a solvothermal method emit bright, deep blue photoluminescence at 447 nm. The photoluminescence (PL), photoluminescence excitation (PLE), and absorption spectra demonstrate that Sb3+ doping effectively activate the intrinsic "dark self-trapped exciton (STE)," leading to an impressive photoluminescence quantum yield (PLQY) value of 78.31% for 1% Sb3+ doping. Furthermore, the luminescence intensity remains above 92% compared with the fresh sample without secondary phases detected even after 90 days under environmental conditions. To expand the emission spectra, rare-earth Sm3+ is further incorporated into Cs2NaScCl6:1% Sb3+ crystals. The results show that Sb ions not only enhance intrinsic STE luminescence but also serve as sensitizers to boost the red-light emission of Sm3+, leading to a significant 500-fold increase in red emission intensity. Finally, the PLQY reaches a stunning 86.78%. These findings provide valuable insights in the design of Sb ion-doped lead-free double perovskites, broadening the application fields in various optoelectronic devices.

2.
Angew Chem Int Ed Engl ; 63(14): e202319051, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38305690

RESUMO

The design of aqueous zinc (Zn) chemistry energy storage with high rate-capability and long serving life is a great challenge due to its inhospitable coordination environment and dismal interfacial chemistry. To bridge this big gap, herein, we build a highly reversible aqueous Zn battery by taking advantages of the biomass-derived cellulose nanocrystals (CNCs) electrolyte additive with unique physical and chemical characteristics simultaneously. The CNCs additive not only serves as fast ion carriers for enhancing Zn2+ transport kinetics but regulates the coordination environment and interface chemistry to form dynamic and self-repairing protective interphase, resulting in building ultra-stable Zn anodes under extreme conditions. As a result, the engineered electrolyte system achieves a superior average coulombic efficiency of 97.27 % under 140 mA cm-2, and steady charge-discharge for 982 h under 50 mA cm-2, 50 mAh cm-2, which proposes a universal pathway to challenge aqueous Zn chemistry in green, sustainable, and large-scale applications.

3.
J Phys Condens Matter ; 36(1)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37738991

RESUMO

Spin polarization of two-dimensional electron gas (2DEG) at the interface of EuTiO3/SrTiO3(STO) heterostructures has been theoretical predicted and experimentally observed via x-ray magnetic circular dichroism and polarized x-ray absorption spectroscopy, which, however, is lack of magnetotransport evidence. Here, we report the fabrication of high-quality EuTiO3/STO heterostructures by depositing antiferromagnetic insulating EuTiO3thin films onto STO substrates. Shubnikov-de Haas oscillation, Hall, and magnetoresistance (MR) measurements show that the interface is not only highly conducting, with electron mobility up to5.5×103cm2V-1s-1at 1.8 K, but also shows low-field hysteretic MR effects. MR of ∼9% is observed at 1.8 K and 20 Oe, which is one order of magnitude higher than those observed in other spin-polarized 2DEG oxide systems. Moreover, the heterostructures show ferromagnetic hysteresis loops. These results demonstrate that the high-mobility 2DEG is spin polarized, whose origin is attributed to the interfacial Ti3+-3dstates due to oxygen deficiency and the exchange interactions between interfacial Eu spins and itinerant Ti-3delectrons.

4.
Phys Chem Chem Phys ; 25(10): 7550, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36848140

RESUMO

Correction for 'Magnetotransport and magnetic properties of Cr-modified Mn2Sb epitaxial thin films' by Ting-Wei Chen et al., Phys. Chem. Chem. Phys., 2023, 25, 5785-5794, https://doi.org/10.1039/D2CP05442F.

5.
Phys Chem Chem Phys ; 25(7): 5785-5794, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36744652

RESUMO

High-quality Mn2-xCrxSb (x = 0.01, 0.04, and 0.1) epitaxial thin films were grown on SrTiO3 (STO) (001) single-crystal substrates using molecular beam epitaxy. Magnetotransport and magnetic measurements reveal that the x = 0.01 sample undergoes a quasi-ferrimagnetic (I) [Q-FIM(I)]-to-ferrimagnetic (II) [FIM(II)] spin reorientation (SR) transition and a giant magnetoresistance (MR) associated first-order ferrimagnetic(II)-to-antiferromagnetic (AFM) phase transition upon cooling, resulting in the AFM ground state with a weak in-plane net moment. Upon increasing the doping level from x = 0.01 to 0.1, both the SR transition and the first-order magnetic transition are suppressed. For x = 0.1, the former transition is suppressed, leaving only the Q-FIM(I)-to-AFM transition within the whole temperature region. TAFM-FIM shows almost similar changes upon the application of either in-plane or out-of-plane magnetic fields. TAFM-FIM values of the x = 0.01 and 0.04 samples are much higher than those of the Mn2-xCrxSb bulk with similar doping levels, which can be understood by the clamping effect from STO substrates. For each thin-film sample, the MR effect is observed near TAFM-FIM and disappears in the high temperature Q-FIM(I) phase and low temperature AFM phase, indicating that MR is related to the spin-dependent electron scattering during the first-order magnetic phase transition. Based on the magnetotransport and magnetic data, a magnetic phase diagram is established for the Mn2-xCrxSb films in the low doping level region.

6.
Comput Intell Neurosci ; 2022: 5884868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35761868

RESUMO

To realize the predictive control of coal preparation quality and ensure that the quality of washing products is close to the minimum coal quality requirement of coal blending to the greatest extent is one of the important means to maximize production and maintain the interests of customers and enterprises. Therefore, the feasibility of introducing the double response surface method and multiobjective genetic algorithm to solve the aforementioned problems is further discussed. By selecting the controllable factors and noise factors affecting the output and determining their respective value levels, the product table method is used to design the robust parameter design test, and the experimental results are obtained, according to the experimental data, the second-order polynomial model of the mean and standard deviation of each response characteristic is established, and the effectiveness of the model is analyzed. Then, the double-response optimization function of each response characteristic is established according to the type of response characteristic. Finally, the corresponding parameter values are solved by multiobjective genetic algorithm. The internal and external surface method is used to design and run 60 tests. Through optimization analysis, the robust parameter settings are 150.68 kpa, 0.18143.73 kpa, and 30%, and the optimal output is ash 8.499%, which yields 69.54%, meeting the requirements of stakeholders. Moreover, compared with the traditional optimization design method, the superiority of the proposed method is verified, which shows that this method is conducive to the transformation of the coal preparation plant from fire-fighting quality management to preventive quality management and provides support for the accurate control and systematic management of the production process of the coal preparation plant.


Assuntos
Tempestades Ciclônicas , Algoritmos , Carvão Mineral
7.
ACS Appl Mater Interfaces ; 13(49): 58949-58955, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34854300

RESUMO

Stoichiometric Cr2Se3 single crystals are particular layer-structured antiferromagnets, which possess a noncollinear spin configuration, weak ferromagnetic moments, moderate magnetoresistance (MR ∼14.3%), and poor metallic conductivity below the antiferromagnetic phase transition. Here, we report an interesting >16 000% colossal magnetoresistance (CMR) effect in Ti (1.5 atomic percent) lightly doped Cr2Se3 single crystals. Such a CMR is approximately 1143 times larger than that of the stoichiometric Cr2Se3 crystals and is rarely observed in layered antiferromagnets and is attributed to the frustrated spin configuration. Moreover, the Ti doping not only dramatically changes the electronic conductivity of the Cr2Se3 crystal from a bad metal to a semiconductor with a gap of ∼15 meV but also induces a change in the magnetic anisotropy of the Cr2Se3 crystal from strong out-of-plane to weak in-plane. Further, magnetotransport measurements reveal that the low-field MR scales with the square of the reduced magnetization, which is a signature of CMR materials. The layered Ti:Cr2Se3 with the CMR effect could be used as two-dimensional (2D) heterostructure building blocks to provide colossal negative MR in spintronic devices.

8.
Mar Pollut Bull ; 172: 112795, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34391009

RESUMO

In this paper, a marine environmental sensitivity index system was constructed based on three factors: the marine biological species sensitivity, the marine ecological value sensitivity and the social and economic sensitivity. Combined with numerical simulations of 137Cs in the Beibu Gulf under the condition of a level-7 nuclear accident, a comprehensive risk assessment of marine radioactivity under the simulated accident in the Beibu Gulf was carried out. The results show that the areas at high risk and medium-to-high risk to marine radioactivity are mainly concentrated within 30 km of the Fangchenggang Nuclear Power Plant. The medium-risk areas are mainly distributed in sea areas within 30-50 km of the nuclear power plant, and the other sea areas are low-risk areas. The distribution of the risk sources and the characteristics of the regional tidal currents are the main factors affecting the magnitude and distribution of the comprehensive risk of regional marine radioactivity.


Assuntos
Radioatividade , Poluentes Químicos da Água , China , Monitoramento Ambiental , Medição de Risco , Poluentes Químicos da Água/análise
9.
BMC Psychiatry ; 21(1): 378, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34320935

RESUMO

BACKGROUND: A motivation dimension of the core psychiatric symptom anhedonia additional has been suggested. The Temporal Experience of Pleasure Scale (TEPS) has been reported to assess anticipatory and consummatory pleasure separately in multiple factor-structure models. This study explored the factor structure of a Chinese version of the 18-item TEPS and further explored the measurement invariance of the TEPS across sex and clinical status (non-clinical, psychiatric). METHODS: Best-fit factor structure of the TEPS was examined in a non-clinical cohort of 7410 undergraduates, randomized into sample 1 (N = 3755) for exploratory factor analysis (EFA) and sample 2 (N = 3663) for confirmatory factor analysis (CFA). Additionally, serial CFA was conducted to evaluate measurement invariance across sex and between clinical (N = 313) and non-clinical (N = 341) samples. RESULTS: EFA supported a new four-factor structure with a motivation component, based on the original two-factor model (consummatory pleasure with/without motivation drive, anticipatory pleasure with/without motivation drive). CFA confirmed the four-factor model as the best-fit structure and revealed a second-order hierarchy in non-clinical and clinical samples. Full scalar invariance was observed across clinical and non-clinical samples and across sex in the clinical sample; only partial scalar invariance was observed across sex in the non-clinical sample. CONCLUSIONS: A four-factor structured TEPS can assess motivation-driving dimensions of anticipatory and consummatory pleasure, consistent with the recently advanced multidimensional structure of anhedonia. CFA and measurement invariance results support application of the TEPS for assessing motivation aspects of anhedonia.


Assuntos
Prazer , Universidades , China , Humanos , Psicometria , Reprodutibilidade dos Testes , Estudantes
10.
Front Psychiatry ; 12: 635214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841206

RESUMO

The Personality Inventory for the DSM-5 (PID-5) is an established tool for assessing personality disorder (PD) traits that was developed based on section III of the DSM-5. It is composed of 220 items, organized into 25 facets, which are distributed among five domains. The psychometric properties of the Chinese version of the PID-5 remain to be demonstrated. Two samples were embodied in this study that included 3,550 undergraduates and 406 clinical patients. To probe the structure of the PID-5, parallel analyses were conducted to explore the unidimensionality of its 25 facets and a series of confirmatory factor analyses (CFAs) were carried out to confirm the 25 lower-order facets and their distribution among five higher-order domains. Then, the PID-5 was employed to measure the DSM-5 and ICD-11 trait models and to explore the relationship of DSM-IV categorical PDs with DSM-5 and ICD-11 personality traits. Correlation and regression analyses were conducted to probe how well DSM-IV categorical PDs correspond with maladaptive personality traits specified in the DSM-5 and five ICD-11 domains. The respective average internal reliability coefficients of the 25 facets obtained for undergraduate and clinical patient samples were 0.76 and 0.81, those obtained for the five DSM-5 domains were 0.89 and 0.91, and those obtained for the five ICD-11 domains were 0.87 and 0.89. Serial CFAs confirmed the rationality of the PID-5's lower-order 25-facet structure and higher-order five-domain structure in both samples. Correlation and regression analyses showed that DSM-5 specified traits explain the variance in PD presentation with a manifold stronger correlation (R 2 = 0.24-0.44) than non-specified traits (R 2 = 0.04-0.12). Overall, the PID-5 was shown to be a reliable, stable, and structurally valid assessment tool that captures pathological personality traits related to DSM-5 and ICD-11 PDs.

11.
BMC Psychiatry ; 21(1): 107, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596861

RESUMO

BACKGROUND: The Personality Inventory for DSM-5 Brief Form (PID-5-BF) is a 25-item measuring tool evaluating maladaptive personality traits for the diagnosis of personality disorders(PDs). As a promising scale, its impressive psychometric properties have been verified in some countries, however, there have been no studies about the utility of the PID-5-BF in Chinese settings. The current study aimed to explore the maladaptive personality factor model which was culturally adapted to China and to examine psychometric properties of the PID-5-BF among Chinese undergraduate students and clinical patients. METHODS: Seven thousand one hundred fifty-five undergraduate students and 451 clinical patients completed the Chinese version of the PID-5-BF. Two hundered twenty-eight students were chosen randomly for test-retest reliability at a 4-week interval. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted to discover the most suitable factor structure in China, measurement invariance(MI), internal consistency, and external validity were also calculated. RESULTS: The theoretical five-factor model was acceptable, but the exploratory six-factor model was more applicable in both samples (Undergraduate sample: CFI = 0.905, TLI = 0.888, RMSEA = 0.044, SRMR = 0.039; Clinical sample: CFI = 0.904, TLI = 0.886, RMSEA = 0.047, SRMR = 0.060). In the Chinese six-factor model, the Negative Affect domain was divided into two factors and the new factor was named "Interpersonal Relationships", which was in line with the Big-Six Personality model in Chinese. Measurement invariance across non-clinical and clinical sample was established (configural, weak, strong MI, and partial strict MI). Aside from acceptable internal consistency (Undergraduate sample: alpha = 0.84, MIC = 0.21; Clinical sample: alpha = 0.86, MIC = 0.19) and test-retest reliability(0.73), the correlation between the 25-item PID-5-BF and the 220-item PID-5 was significant(p < 0.01). The six PDs measured by Personality diagnostic questionnaire-4+ (PDQ-4+) were associated with and predicted by expected domains of PID-5-BF. CONCLUSIONS: Both the theoretical five-factor model and the exploratory six-factor model of the PID-5-BF were acceptable to the Chinese population. The five-factor model could allow for comparison and integration with other work on the original theoretical model. However, the Chinese six-factor structure may be more culturally informed in East Asian settings. In sum, the PID-5-BF is a convenient and useful screening tool for personality disorders.


Assuntos
Estudantes , China , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Inventário de Personalidade , Psicometria , Reprodutibilidade dos Testes
12.
J Affect Disord ; 281: 759-766, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33229024

RESUMO

BACKGROUND: Anhedonia, a key symptom of depression and schizophrenia, has emerged as a potential endophenotype. The aim of this study was to evaluate the psychometric properties of a Chinese version of the Snaith-Hamilton Pleasure Scale(SHAPS), a self-report anhedonia scale, in a non-clinical sample and clinical sample inclusive of major depressive disorder (MDD), schizophrenia, or a personality disorder. METHODS: A total of 4,722 undergraduate students and 352 clinical patients participated in this study. Internal consistency was assessed by calculating Cronbach's α and mean inter-item correlation (MIC) values. Test-retest reliability and convergent validity were assessed with Pearson r coefficients. The best fitting of six potential factor-structure models was determined by confirmatory factor analysis (CFA). Measurement invariance across genders and samples was determined by multi-group CFA. RESULTS: Internal consistency of the Chinese version of the SHAPS was acceptable in non-clinical (Cronbach's α = 0.90) and clinical (Cronbach's α = 0.91) samples. Four-week interval test-retest reliability was 0.60. Moreover, the Spanish four-factor structure had the best fit indexes in both samples. Scalar invariance was established across genders as well as across non-clinical sample and clinical sample. SHAPS was significantly related with the Temporal Experience of Pleasure Scale (TEPS) and Beck Depression Inventory (BDI). LIMITATIONS: There was a restricted scope of convergent validity and the size of clinical sample is relatively small, psychometric properties in elderly sample is also required. CONCLUSION: The Chinese version of the SHAPS is a reliable, effective, simple and convenient tool for assessing and screening for anhedonia.


Assuntos
Transtorno Depressivo Maior , Prazer , Idoso , Anedonia , China , Transtorno Depressivo Maior/diagnóstico , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes
13.
BMC Psychiatry ; 20(1): 529, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33167901

RESUMO

BACKGROUND: Anhedonia is a core clinical symptom of mental disorders. The Revised Physical Anhedonia Scale (RPAS) and the Revised Social Anhedonia Scale (RSAS) have been applied in clinical and non-clinical samples since 1980s. However, the construct of a unified RPAS&RSAS for comprehensive measurement of anhedonia has never been explored. Therefore, the purpose of our study was to examine the factor structure of the unified RPAS&RSAS among undergraduates and clinical patients. METHODS: A total of 3435 undergraduates from two universities and 294 clinical patients with mental disorders had completed the Chinese version of the RPAS and the RSAS. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were each conducted to reveal the constructs of the RPAS and the RSAS. CFA was used to evaluate first- and second-order models for the unified RPAS&RSAS in undergraduates and clinical patients. The internal consistency and test-retest reliability of the RPAS and the RSAS were also evaluated. RESULTS: EFA and CFA indicated 2-factor structures for RPAS and RSAS, with the factors being defined as anticipatory anhedonia and consummatory anhedonia. The second-order model of the unified RPAS&RSAS in the undergraduates and clinical patients both had satisfactory fit index values (Undergraduate sample: CFI = 0.901, TLI = 0.899, RMSEA = 0.055, SRMR = 0.086; Clinical sample: CFI = 0.922, TLI = 0.911, RMSEA = 0.052, SRMR = 0.078). The psychometric robustness of the RPAS&RSAS were confirmed by high internal consistency and test-retest reliability values. CONCLUSIONS: The unified RPAS&RSAS with a second-order structure was confirmed in both undergraduates and clinical samples in Chinese. The construct of anhedonia was refreshed as covering physical and social domains, and each of them includes both anticipatory and consummatory components.


Assuntos
Anedonia , China , Análise Fatorial , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 71(2): 588-91, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18356098

RESUMO

The luminescence properties of four europium chelates with increasing benzene ring substituents ligand in poly(methylmethacrylate) (PMMA) have been investigated by fluorescence emission spectra and lifetime measurements. According to the fluorescence emission spectra, the Judd-Ofelt parameters Omega2, Omega4 of europium chelates-doped PMMA have been calculated and the radiative properties were also presented. It showed that the increase of benzene ring substituents in ligand can increase the metastable state lifetime tau(m), the luminescence quantum yield eta and the stimulated emission cross-section sigma of 5D0-->7F2 transition.


Assuntos
Benzeno/química , Compostos Organometálicos/química , Polimetil Metacrilato/química , Ligantes , Estrutura Molecular , Espectrometria de Fluorescência
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