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1.
Langmuir ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39264301

RESUMEN

Due to the easy oxidation of Sn2+, which leads to form tin vacancy defects and poor perovskite film quality, caused by the rapid crystallization rate in tin-based perovskite solar cells (PSCs), their efficiency lags far behind that of lead-based PSCs. To improve the photovoltaic (PV) performance and stability of FA0.9PEA0.1SnI3-based PSCs (T-PSCs), a small amount of Pb(SCN)2 is introduced into a perovskite precursor as an antioxidant, and acetaminophen (ACE) with various functional groups is used to modify a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)/perovskite interface. The results show that the Pb(SCN)2 additive and ACE interfacial modification can not only optimize energy level alignment in T-PSCs but also inhibit Sn2+ oxidation to reduce the trap-state density, resulting in promoted carrier transport. The synergetic effect of the Pb(SCN)2 antioxidant and ACE interfacial modification significantly reduces nonradiative recombination and improves the PV performance and stability of T-PSCs. Consequently, the unsealed T-PSCs with the Pb(SCN)2 additive and ACE modification achieve a champion efficiency of 12.04% and maintain 99% of their initial PCE after being stored in N2 for more than 2100 h, while reference T-PSCs demonstrate a champion PCE of 6.20% and retain only 72% of its initial PCE. Moreover, the modified T-PSCs without encapsulation demonstrate much better stability in humid air.

2.
Clin Nutr ESPEN ; 61: 22-27, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38777437

RESUMEN

BACKGROUND AND AIMS: We aimed to examine the association between nutritional status, assessed by height/length and body weight for age and sex, and Epstein-Barr virus (EBV) viremia in children underwent liver transplantation. METHODS: Nutritional status was determined by total score of age- and sex-specific height/length and body weight: < (-2 SD) as "2 points", (-2 SD to -1 SD) as "1 point", and ≥ (-1SD) as "0 point". Children were further classified into three groups: malnutrition (4 points), risk of malnutrition (1-3 points), and normal (0 point). EBV viremia were confirmed by real time quantitative PCR method if EBV burden was ≥400 copies/ml. RESULTS: A total number of 896 children (414 boys and 482 girls, medium age 8 months) were included in the study. The medium height was 65.0 cm while medium body weight was 7.0 kg. The prevalence of EBV viremia was 54.6% during follow up. Comparing with children with normal nutritional status, the adjusted odds ratios for the risk of EBV viremia was 2.14 (95% CI: 1.44, 3.19) in children with risk of malnutrition, and 2.29 (95% CI: 1.54, 3.40) in children with malnutrition. Each point increase of nutritional score was associated with a 21% higher risk of EBV viremia (odd ratios = 1.21; 95% CI: 1.10, 1.34) in fully adjusted model. CONCLUSIONS: Nutritional score was associated with EBV viremia in children underwent liver transplantation.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Trasplante de Hígado , Estado Nutricional , Viremia , Humanos , Femenino , Masculino , Estudios Transversales , Estudios Retrospectivos , Lactante , Preescolar , Niño , Desnutrición , Peso Corporal , Prevalencia , Estatura , Factores de Riesgo
3.
ACS Appl Mater Interfaces ; 15(38): 45064-45075, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37710994

RESUMEN

Tin-based perovskite solar cells (T-PSCs) have become the star photovoltaic products in recent years due to their low environmental toxicity and superior photovoltaic performance. However, the easy oxidation of Sn2+ and the energy level mismatch between the perovskite film and charge transport layer limit its efficiency. In order to regulate the microstructure and photoelectric properties of tin-based perovskite films to enhance the efficiency and stability of T-PSCs, guanidinium bromide (GABr) and organic Lewis-based additive methylamine cyanate (MAOCN) are introduced into the FA0.9PEA0.1SnI3-based perovskite precursor. A series of characterizations show that the interactions between additive molecules and perovskite mutually reconcile to improve the photovoltaic performance of T-PSCs. The introduction of GABr can adjust the band gap of the perovskite film and energy level alignment of T-PSCs. They significantly increase the open-circuit voltage (Voc). The MAOCN material can form hydrogen bonds with SnI2 in the precursor, which can inhibit the oxidation of Sn2+ and significantly improve the short-circuit current density (Jsc). The synergistic modulation of the dual additives reduces the trap-state density and improves photovoltaic performance, resulting in an increased champion efficiency of 9.34 for 5.22% of the control PSCs. The unencapsulated T-PSCs with GABr and MAOCN dual additives prepared in the optimized process can retain more than 110% of their initial efficiency after aging for 1750 h in a nitrogen glovebox, but the control PSCs maintain only 50% of their initial efficiency kept in the same conditions. This work provides a new perspective to further improve the efficiency and stability of T-PSCs.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 268: 120655, 2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-34857467

RESUMEN

A new perovskite BaLaMgTaO6:Mn4+ (BLMTO:Mn4+) red phosphor was synthesized for the first time via the high-temperature solid-state method. The emission band of the phosphor ranges from 650 to 750 nm, which matches well with the absorption band of PFR and PR. By doping of Bi3+ and Ca2+ ions in the BLMTO:Mn4+ phosphor, a 4.76-fold enhancement in the luminescence emission intensity was achieved. The optimized BLMTO:0.5%Mn4+, 1.5%Bi3+, 2%Ca2+ phosphor exhibited a high quantum efficiency of 65% and a high color purity of 98.1% with the chromaticity coordinate (CIE) at (0.733, 0.267). Finally, a LED device was fabricated with the BLMTO:0.5%Mn4+, 1.5%Bi3+, 2%Ca2+ phosphor for further agricultural lighting, which emits warm white light with a low color temperature of 3549 K. The result indicates that the BLMTO:Mn4+, Bi3+, Ca2+ phosphors have a potential for applications in agricultural cultivations.


Asunto(s)
Luminiscencia , Sustancias Luminiscentes , Luz , Iluminación , Fósforo
5.
J Environ Manage ; 168: 245-51, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26720720

RESUMEN

Crop straw biochar incorporation may be a sustainable method of amending soil, but feedstock-related Cd and Pb content is a major concern. We investigated the effects of heavy metal-rich (RC) and -free biochar (FC) on the phytoavailability of Cd and Pb in two acidic metalliferous soils. Biochar significantly increased soil pH and improved plant growth. Pb in soil and plant tissues significantly decreased after biochar application, and a similar pattern was observed for Cd after FC application. RC significantly increased NH4NO3-extractable Cd in both lightly contaminated (YBS) and heavily contaminated soils (RS). The Cd content of plants grown on YBS increased, whereas it decreased on RS. The Cd and Pb input-output balance suggested that RC application to YBS might induce a soil Cd accumulation risk. Therefore, identifying heavy metal contamination in biochar is crucial before it is used as a soil amendment.


Asunto(s)
Cadmio/química , Carbón Orgánico , Plomo/química , Metales Pesados/química , Contaminantes del Suelo/química , Suelo/química , Humanos
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