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1.
Adv Mater ; : e2003164, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33164236

RESUMO

Exciton lifetime (τ) is crucial for the migration of excitons to donor/acceptor interfaces for subsequent charge separation in organic solar cells (OSCs); however, obvious prolongation of τ has rarely been achieved. Here, by introducing a solid additive 9-fluorenone-1-carboxylic acid (FCA) into the active layer, which comprises a nonfullerene acceptor, 3,9-bis(2-methylene-((3-(1,1-dicyanomethylene)-6/7-methyl)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IT-M), τ is substantially prolonged from 491 to 928 ps, together with obvious increases in fluorescence intensity and quantum yield. Time-resolved transient infrared spectra indicate the presence of an intermolecular vibrational coupling between the electronic excited state of IT-M and the electronic ground state of FCA, which is first observed here and which can suppress the internal conversion process. IT-M-based OSCs display an improved short-circuit current and fill factor after the addition of FCA. Thus, the power conversion efficiency is increased, particularly for devices with a large donor/acceptor ratio of 1:4, whose efficiency is increased by 56%. This study describes a novel method, which is also applicable to other nonfullerene acceptors, for further improving the performance of OSCs without affecting their morphology and light absorption properties.

2.
ACS Appl Mater Interfaces ; 12(47): 53021-53028, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33170610

RESUMO

As a well-known electron-withdrawing group, benzo[c][1,2,5]thiadiazole (BT) has been intensively studied and adopted to construct polymer donors with tunable band gaps. However, polymer solar cells (PSCs) with BT-based polymer donors, limited by the weak absorption and inflexible energy level of fullerene derivatives, usually suffer mediocre power conversion efficiencies (PCEs). Here, through subtly tailoring a BT unit with asymmetric fluoro and alkyloxy groups and judiciously pairing a BT-based polymer donor with three narrow band gap non-fullerene acceptors (e.g., IEICO-4F, ITOIC-2F, and IDTCN-O), active layers with complementary absorption spectra, small lowest unoccupied molecular orbital (LUMO) offsets, and preferred morphologies have been achieved. Consequently, PSCs with excellent Jsc values (over 20 mA/cm2) and high PCEs up to 12.33% have been obtained. To the best of our knowledge, the value of 12.33% is among the highest PCEs for BT-based polymers in binary PSCs so far. This work demonstrates that the cooperative effect of energy levels, absorption spectra, and morphologies between the donors and acceptors is crucial for governing the performance of organic photovoltaics.

3.
Sci Rep ; 10(1): 17477, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33060793

RESUMO

We present a new simple and efficient method for correlation of unevenly and differently sampled data. This new method overcomes problems with other methods for correlation with non-uniform sampling and is an easy modification to existing correlation based codes. To demonstrate the usefulness of this new method to real-world examples, we apply the method with good success to two glaciological examples to map the ages from a well-dated ice core to a nearby core, and by tracing isochronous layers within the ice sheet measured from ice-penetrating radar between the two ice core sites.

4.
Gene Ther ; 27(7-8): 349-359, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32681137

RESUMO

Sensorineural hearing loss, the most common form of hearing impairment, is mainly attributable to genetic mutations or acquired factors, such as aging, noise exposure, and ototoxic drugs. In the field of gene therapy, advances in genetic and physiological studies and profound increases in knowledge regarding the underlying mechanisms have yielded great progress in terms of restoring the auditory function in animal models of deafness. Nonetheless, many challenges associated with the translation from basic research to clinical therapies remain to be overcome before a total restoration of auditory function can be expected. In recent years, Chinese research teams have promoted various developmental efforts in this field, including gene sequencing to identify additional potential loci that cause deafness, studies to elucidate the underlying molecular mechanisms, and research to optimize vectors and delivery routes. In this review, we summarize the state of the field and focus mainly on the progress of gene therapy in animal model studies and the optimization of therapeutic strategies in China.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32337755

RESUMO

INTRODUCTION: Physical inactivity is a risk factor for many noncommunicable diseases. As reported by the World Health Organisation, 81% of children worldwide are physically inactive. Environmental factors, such as neighbourhood walkability, can shape people's physical activity (PA) behaviour. This study explored the association between neighbourhood walkability and after-school PA among Australian schoolchildren. METHODS: The Department for Education and Child Development (DECD) distributed the survey to 189 schools across South Australia to assess the health and well-being of schoolchildren aged between 8 and 14 years. Neighbourhood was defined as an area corresponding to a four digit postcode, and its walkability was measured using Walk Score® . The association between neighbourhood walkability and after-school PA was analysed using multinomial logistic regression adjusted for age, gender, SEIFA score, number of days of TV watching, number of times of eating junk food, neighbourhood safety and children's weight status. RESULTS: Children residing in highly walkable areas (walker's paradise) compared to car-dependent areas had higher odds (OR(95%CI)) of engaging in after-school PA three (1.216 (1.029, 1.436), P = .021), four (1.287 (1.064, 1.557), P = .009) and five times a week (1.230 (1.030, 1.133), P = .022) compared to children never participating in PA. CONCLUSION: Living in highly walkable areas (walker's paradise), compared to living in car-dependent areas was associated with higher levels of after-school PA. So what? Creating walkable neighbourhoods with greater access to amenities, services and public transportation may help increase after-school PA among schoolchildren.

6.
Nat Commun ; 10(1): 3038, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292441

RESUMO

Non-fullerene fused-ring electron acceptors boost the power conversion efficiency of organic solar cells, but they suffer from high synthetic cost and low yield. Here, we show a series of low-cost noncovalently fused-ring electron acceptors, which consist of a ladder-like core locked by noncovalent sulfur-oxygen interactions and flanked by two dicyanoindanone electron-withdrawing groups. Compared with that of similar but unfused acceptor, the presence of ladder-like structure markedly broadens the absorption to the near-infrared region. In addition, the use of intramolecular noncovalent interactions avoids the tedious synthesis of covalently fused-ring structures and markedly lowers the synthetic cost. The optimized solar cells displayed an outstanding efficiency of 13.24%. More importantly, solar cells based on these acceptors demonstrate very low non-radiative energy losses. This research demonstrates that low-cost noncovalently fused-ring electron acceptors are promising to achieve high-efficiency organic solar cells.

7.
Asian-Australas J Anim Sci ; 30(8): 1135-1142, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28111435

RESUMO

OBJECTIVE: The objective of this study was to evaluate effects of heat treatment and soybean oil inclusion on protein oxidation of soy protein isolate (SPI) and of oxidized protein on redox status of broilers at an early age. METHODS: SPI mixed with soybean oil (SPIO) heated at 100°C for 8 h was used to evaluate protein oxidation of SPI. A total of two hundred and sixteen 1-day-old Arbor Acres chicks were divided into 3 groups with 6 replicates of 12 birds, receiving basal diet (CON), heat-oxidized SPI diet (HSPI) or mixture of SPI and 2% soybean oil diet (HSPIO) for 21 d, respectively. RESULTS: Increased protein carbonyl, decreased protein sulfhydryl of SPI were observed as heating time increased in all treatments (p<0.05). Addition of 2% soybean oil increased protein carbonyl of SPI at 8 h heating (p<0.05). Dietary HSPI and HSPIO decreased the average daily gain of broilers as compared with the CON (p<0.05). Broilers fed HSPI and HSPIO exhibited decreased glutathione (GSH) in serum, catalase activity and total sulfhydryl in liver and increased malondialdehyde (MDA) and protein carbonyl in serum, advanced oxidation protein products (AOPPs) in liver and protein carbonyl in jejunal mucosa as compared with that of the CON (p<0.05). Additionally, broilers receiving HSPIO showed decreased glutathione peroxidase activity (GSH-Px) in serum, GSH and hydroxyl radical scavenging capacity in liver, GSH-Px activity in duodenal mucosa, GSH-Px activity and superoxide anion radical scavenging capacity in jejunal mucosa and increased AOPPs in serum, MDA and protein carbonyl in liver, MDA and AOPPs in jejunal mucosa (p<0.05). CONCLUSION: Protein oxidation of SPI can be induced by heat and soybean oil and oxidized protein resulted in redox imbalance in broilers at an early age.

8.
Anim Sci J ; 87(10): 1291-1297, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26800429

RESUMO

Soy protein isolate (SPI) mixed with soybean oil (SPIO) incubated at 100°C for 8 h was used to evaluate changes of solubility and digestibility of SPI in vitro and digestive function in broilers at an early age. Arbor Acres broilers were allocated to three groups with six replicates of 12 birds, receiving basal diet (CON), 8 h heat-oxidized SPI diet (HSPI) and 8 h heat-oxidized mixture of SPI and 2% soybean oil diet (HSPIO) for 21 days, respectively. Nitrogen solubility index (NSI) declined and soybean oil accelerated the decline of NSI during incubation (P < 0.05). Decreased in vitro digestibility of dry matter (DM) and crude protein (CP) were observed in SPIO (P < 0.05). HSPI and HSPIO decreased body weight gain, relative jejunum weight and pancreatic trypsin activity at day 21 (P < 0.05). HSPIO decreased anterior intestinal trypsin activity at day 14 and amylase and trypsin activity at day 21, pancreatic amylase activity at day 21 and apparent digestibility of DM, organic matter and CP of broilers from days 18 to 20 (P < 0.05). Heat treatment and soybean oil could induce oxidative modification of SPI, and oxidized SPI negatively affected growth and digestion of broilers. © 2016 Japanese Society of Animal Science.


Assuntos
Envelhecimento/fisiologia , Ração Animal , Galinhas/crescimento & desenvolvimento , Galinhas/fisiologia , Dieta/veterinária , Digestão , Temperatura Alta/efeitos adversos , Proteólise , Óleo de Soja , Proteínas de Soja , Animais , Peso Corporal , Técnicas In Vitro , Oxirredução , Solubilidade , Óleo de Soja/efeitos adversos , Proteínas de Soja/química , Fatores de Tempo
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