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1.
J Org Chem ; 89(12): 8734-8744, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38814709

RESUMO

A gold-catalyzed oxidative rearrangement of propargyl alcohols, derived from commercially available cyclohex-2-en-1-ones and alkynes, was successfully developed for the efficient synthesis of seven-membered rings. Thorough investigations were conducted to optimize the reaction conditions and evaluate its compatibility with various functional groups. Additionally, this methodology was applied to the formal total synthesis of guanacastepene A, demonstrating its practical utility in complex natural product synthesis. This versatile and efficient approach opens up new possibilities for the construction of diverse seven-membered ring systems, providing valuable building blocks for further exploration in drug discovery and the synthesis of intricate molecules.

2.
J Org Chem ; 89(5): 3331-3344, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363745

RESUMO

A gold(I)-catalyzed hydroamination/cycloisomerization cascade reaction was developed to yield indolizino[8,7-b]indole and indolo[2,3-a]-quinolizine derivatives from 2-ethynyltryptamides. The optimal conditions were determined by condition screening, and the functional group tolerances of these reactions were explored based on synthetic substrates. An insight into the explanation on the selectivity of the ring closure was obtained by density functional theory calculations. A plausible mechanism for the cascade reactions was proposed. Derivatization of the indolizino[8,7-b]indole and total synthesis of nauclefidine demonstrated the practicality of this strategy.

3.
Int J Nurs Pract ; 30(3): e13226, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38128910

RESUMO

BACKGROUND: The high incidence of malnutrition in patients undergoing colorectal cancer surgery can lead to unplanned weight loss, sarcopenia and reduced grip strength to the extent that it can seriously affect the prognosis of colorectal cancer patients. OBJECTIVE: This study investigated the effect of oral nutritional supplements (ONS) on the prevalence of grip strength, unplanned weight loss and sarcopenia in patients undergoing colorectal cancer surgery. METHODS: We systematically searched randomized controlled studies from CINAHL, PubMed, Embase, Cochrane and Web of Science and three Chinese databases (CNKI, Wan-Fang database, VIP database) from database creation to September 2023. The risk of bias in individual studies was assessed using the Cochrane Collaboration tool, and the certainty of evidence was assessed using the five GRADE criteria. Statistical analysis was performed using the RevMan 5.3 software, and information that could not be meta-analysed was reviewed in the form of a literature summary. RESULTS: Eleven papers met the inclusion criteria with a combined sample size of 1070 cases, including 532 cases in the trial group and 538 cases in the control group. Four papers reported the effect of ONS on grip strength and included very low-quality evidence supporting no effect of ONS on grip strength. Ten studies reported the effect of ONS on body weight and body mass index (BMI) and included very low-quality evidence supporting a positive ONS on weight and BMI changes. Meta-analysis showed a significant reduction in weight loss (12-15 weeks) and BMI loss (12-15 weeks) in patients with colorectal cancer in the ONS group. The effect of ONS on the prevalence of sarcopenia after hospital discharge was reported in two studies, and meta-analysis showed a significant reduction in the prevalence of postoperative sarcopenia in colorectal cancer patients in the ONS group, but the quality of evidence was low. CONCLUSIONS: This study showed that the use of ONS in patients undergoing surgery for colorectal cancer improved patient weight loss and BMI reduction and reduced the prevalence of postoperative sarcopenia but did not improve patient grip strength. The quality of evidence for inclusion in the article was low or very low, and further studies are needed to provide better evidence.


Assuntos
Neoplasias Colorretais , Suplementos Nutricionais , Estado Nutricional , Humanos , Neoplasias Colorretais/cirurgia , Sarcopenia/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Força da Mão , Desnutrição/prevenção & controle , Desnutrição/epidemiologia , Redução de Peso
4.
J Org Chem ; 88(11): 7179-7187, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37172220

RESUMO

Six 8-oxoprotoberberines were synthesized collectively in four steps with acceptable yields (14-19%), of which the products 8-oxopalmatine, 8-oxopseudopalmatine, 8-oxoberberine, and 8-oxopseudoberberine come from nature. The synthetic route was featured with the In(OTf)3-catalyzed cyclization and Heck coupling. Moreover, the syntheses of the natural products berberine, canadine, and iambertine were achieved via various reductions from 8-oxoberberine, which provided a concise approach to the syntheses of this kind of alkaloids.

5.
J Org Chem ; 88(15): 10586-10598, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37449800

RESUMO

Spiro[indoline-3,3'-pyrrolidine] and spiro[indoline-3,3'-piperidine] derivatives were synthesized in a substitution-controlled manner under the catalysis of cationic gold(I) species in the presence of Hantzsch ester (HEH). The optimal reaction condition was determined by screening, and the functional group tolerances of these two pathways were examined by readily synthetic substrates. The endo and exo selectivities of these cyclizations were elucidated by density functional theory calculations, and a plausible mechanism for these transformations was proposed.

6.
J Org Chem ; 88(9): 5483-5496, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37043684

RESUMO

Density functional theory calculations were applied to predict the pathways of gold(I)-catalyzed cycloisomerization of the indole substrates with 1,6-enynes, which were consistent with the ensuing experimental results. The substitution-controlled synthesis led to the formation of 1H-pyrido[4,3-b]indole and spiro[indoline-3,3'-pyridine] derivatives in a tunable way. The reactions had good functional group tolerances, and a possible mechanism was proposed based on the computational and experimental results.

7.
Cell Biol Int ; 46(5): 755-770, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35077602

RESUMO

Human amniotic epithelial cells (hAECs), one of the stem cells identified from the human placenta, possess numerous advantages and have been considered as an attractive and available cell source for regenerative medicine. Accumulating evidence has showed that cellular senescence was one of the pathogenic hubs of diabetic wound chronicity. Keratinocytes and fibroblasts are the primary cells involved in wound healing. Therefore, in this study, we aimed to investigate the anti-senescence effects of hAECs on keratinocytes and fibroblasts in diabetic wounds. Sustained hyperglycemia impaired cell function and accelerated senescence in vitro. However, this phenotype was rescued by hAECs-conditioned medium (hAECs-CM), with increased migration and proliferation in keratinocytes and fibroblasts and enhanced collagen synthesis and α-smooth muscle actin (α-SMA) production in fibroblasts. In addition, hAECs-CM dramatically inhibited intracellular reactive oxygen species (ROS) and senescence-associated ß-galactosidase (SA-ß-gal) in keratinocytes and fibroblasts under high-glucose (HG) condition. Moreover, hAECs-CM could downregulate the increased RAGE and P21 induced by continuous HG stimulation. Intradermal injection of hAECs in diabetic wounds promoted re-epithelialization and granulation tissue formation, accompanied by decreased P21+ cells and increased PCNA+ cells in epidermis and dermis, as well as promoted collagen deposition and α-SMA expression. Furthermore, CM-Dil-labeled hAECs survived to Day 5 but disappeared by Day 10 in diabetic wounds. These findings indicated that hAECs could inhibit diabetes-induced premature senescence and enhance the function of keratinocytes and fibroblasts via paracrine effects, partly by inhibiting RAGE/P21 signaling pathway. Thus, hAECs targeting cellular senescence induced by a hyperglycemic environment may be a new strategy for the treatment of diabetic wounds.


Assuntos
Diabetes Mellitus , Queratinócitos , Células Cultivadas , Diabetes Mellitus/metabolismo , Fibroblastos/metabolismo , Glucose/metabolismo , Glucose/farmacologia , Humanos , Queratinócitos/metabolismo , Cicatrização
8.
Macromol Rapid Commun ; 43(22): e2200199, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35380177

RESUMO

Although optical engineering strategy has been utilized to optimize average visible transmittance (AVT) of semi-transparent organic solar cells (ST-OSCs), judicious selection of active layer materials should be more direct and basic. Herein, an efficient ternary active layer is constructed with a wide bandgap (3.0 eV) fluorescent polymer FC-S1 as host donor, a middle bandgap polymer PM6 as guest donor, and a narrow bandgap non-fullerene Y6-BO as acceptor. Using FC-S1 as the host donor can allow more visible photons to penetrate the device. In the absence of optical engineering, the ternary ST-OSC with FC-S1:PM6:Y6-BO = 1:0.3:1.5 active layer of 30 nm thickness displays a much higher AVT of 49.28% than that of 32.34% for a PM6:Y6-BO = 1.3:1.5 based binary ST-OSC. The ternary ST-OSC provides a good power conversion efficiency of 6.01%, only slightly lower than 7.15% for the binary ST-OSC. The ternary ST-OSC also demonstrates a color rendering index (CRI) of 87 and a correlated color temperature (CCT) of 6916 K, all better than CRI of 80 and CCT of 9022 K for the binary ST-OSC. Moreover, the backbone of FC-S1 is mainly composed by fluorene and carbazole, two easily-accessible aromatic rings, which would meet low-cost concern of ST-OSCs.


Assuntos
Corantes , Polímeros , Temperatura , Engenharia
9.
J Recept Signal Transduct Res ; 40(5): 471-478, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32340525

RESUMO

Objective: To detect the expression of tripartite motif containing 59 (TRIM59) in human esophageal cancer (EC) tissues and explore whether TRIM59 could affect the progression of EC.Methods: Quantitative PCR and immunohistochemistry assays were performed to detect the expression of TRIM59 in 40 human EC tissues and corresponding non-tumor tissues. The correlations between TRIM59 expression and clinical pathological features of patients with EC were also investigated. CCK-8, colony formation, wound closure, and transwell assays were performed to detect the effects of TRIM59 on EC cells in vitro., Immunoblotting assays were performed to detect the effects of TRIM59 on the expression of mammalian sterile-20-like kinase 4 (MST4) and ERK pathway.Results: We reported increased expression of TRIM59 in human EC tissues, and its expression was correlated with clinical features, including metastasis (p = .011*) and maximum diameter (p = .027*), in patients with EC. We further found that TRIM59 contributed to the proliferation and invasion of EC cells via regulating mammalian sterile-20-like kinase 4 (MST4) expression and ERK pathway.Conclusion: Our data confirmed the involvement of TRIM59 in EC progression and proposed that TRIM59 could serve as a promising therapeutic target for the treatment of EC.


Assuntos
Proliferação de Células/genética , Neoplasias Esofágicas/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas com Motivo Tripartido/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Proc Biol Sci ; 285(1870)2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29298936

RESUMO

Insect pollination in basal angiosperms is assumed to mostly involve 'generalized' insects looking for food, but direct observations of ANITA grade (283 species) pollinators are sparse. We present new data for numerous Schisandraceae, the largest ANITA family, from fieldwork, nocturnal filming, electron microscopy, barcoding and molecular clocks to infer pollinator/plant interactions over multiple years at sites throughout China to test the extent of pollinator specificity. Schisandraceae are pollinated by nocturnal gall midges that lay eggs in the flowers and whose larvae then feed on floral exudates. At least three Schisandraceae have shifted to beetle pollination. Pollination by a single midge species predominates, but one species was pollinated by different species at three locations and one by two at the same location. Based on molecular clocks, gall midges and Schisandraceae may have interacted since at least the Early Miocene. Combining these findings with a review of all published ANITA pollination data shows that ovipositing flies are the most common pollinators of living representatives of the ANITA grade. Compared to food reward-based pollination, oviposition-based systems are less wasteful of plant gametes because (i) none are eaten and (ii) female insects with herbivorous larvae reliably visit conspecific flowers.


Assuntos
Dípteros/anatomia & histologia , Larva/anatomia & histologia , Oviposição/fisiologia , Polinização/fisiologia , Schisandraceae/fisiologia , Animais , Sequência de Bases , China , Código de Barras de DNA Taxonômico , Feminino , Flores/anatomia & histologia , Filogenia , Pólen
11.
J Am Chem Soc ; 139(24): 8355-8363, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28537070

RESUMO

Quinoidal structures incorporating expanded para-quinodimethane (p-QM) units have garnered great interest as functional organic electronic, optical, and magnetic materials. The direct use of the compact p-QM unit as an electronic building block, however, has been inhibited by the high reactivity conveyed by its biradical character. Herein, we introduce a stable p-QM variant, namely p-azaquinodimethane (p-AQM), that incorporates nitrogen atoms in the central ring and alkoxy substituents on the periphery to increase the stability of the quinoidal structure. The succinct synthesis from readily available precursors leads to regio- and stereospecific p-AQMs that can be readily integrated into the backbone of conjugated polymers. The quinoidal character of the p-AQM unit endows the resulting polymers with narrow band gaps and high carrier transport mobilities. The study of a series of copolymers employing different numbers of thiophene units revealed an unconventional trend in band gaps, which is distinct from the widely adopted donor-acceptor approach to tuning the band gaps of conjugated polymers. Theoretical calculations have shed light on the nature of this trend, which may provide a unique class of conjugated polymers with promising optical and electronic properties.

12.
Macromol Rapid Commun ; 36(15): 1393-401, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25966036

RESUMO

Two hydrophilic conjugated polymers, PmP-NOH and PmP36F-NOH, with polar diethanol-amine on the side chains and main chain structures of poly(meta-phenylene) and poly(meta-phenylene-alt-3,6-fluorene), respectively, are successfully synthesized. The films of PmP-NOH and PmP36F-NOH show absorption edges at 340 and 343 nm, respectively. The calculated optical bandgaps of the two polymers are 3.65 and 3.62 eV, respectively, the largest ones so far reported for hydrophilic conjugated polymers. PmP-NOH and PmP36F-NOH also possess deep-lying highest occupied molecular orbital levels of -6.19 and -6.15 eV, respectively. Inserting PmP-NOH and PmP36F-NOH as a cathode interlayer in inverted polymer solar cells with a PTB7/PC71 BM blend as the active layer, high power conversion efficiencies of 8.58% and 8.33%, respectively, are achieved, demonstrating that the two hydrophilic polymers are excellent interlayers for efficient inverted polymer solar cells.


Assuntos
Eletrodos , Polímeros/química , Interações Hidrofóbicas e Hidrofílicas , Energia Solar
13.
Macromol Rapid Commun ; 35(22): 1960-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25284276

RESUMO

DTfBT-Th(3), a new conjugated polymer based on dithienobenzothiadiazole and terthiophene, possesses a bandgap of ≈1.86 eV and a HOMO level of -5.27 eV. Due to strong interchain aggregation, DTfBT-Th(3) can not be well dissolved in chloro-benzene (CB) and o-dichlorobenzene (DCB) at room temperature (RT), but the polymer can be processed from hot CB and DCB solutions of ≈100 °C. In CB, with a lower solvation ability, a certain polymer chain aggregation can be preserved, even in hot solution. DTfBT-Th(3) displays a field-effect hole mobility of 0.55 cm(2) V(-1) s(-1) when fabricated from hot CB solution, which is higher than that of the device processed from hot DCB (0.16 cm(2) V(-1) s(-1) In DTfBT-Th(3) -based polymer solar cells, a good power conversion efficiency from 5.37% to 6.67% can be achieved with 150-300 nm thick active layers casted from hot CB solution, while the highest efficiency for hot DCB-processed solar cells is only 5.07%. The results demonstrate that using a solvent with a lower solvation ability, as a "wet control" process, is beneficial to preserve strong interchain aggregation of a conjugated polymer during solution processing, showing great potential to improve its performances in optoelectronic devices.


Assuntos
Fontes de Energia Elétrica , Polímeros/química , Energia Solar , Tiadiazóis/química , Tiofenos/química , Transistores Eletrônicos , Técnicas Eletroquímicas , Estrutura Molecular , Polímeros/síntese química , Solventes/química , Temperatura
14.
Adv Mater ; 36(16): e2313074, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38237120

RESUMO

Development of polymer donors with simple chemical structure and low cost is of great importance for commercial application of organic solar cells (OSCs). Here, side-chain random copolymer PMQ-Si605 with a simply 6,7-difluoro-3-methylquinoxaline-thiophene backbone and 5% siloxane decoration of side chain is synthesized in comparison with its alternating copolymer PTQ11. Relative to molecular weight (Mn) of 28.3 kg mol-1 for PTQ11, the random copolymer PMQ-Si605 with minor siloxane decoration is beneficial for achieving higher Mn up to 51.1 kg mol-1. In addition, PMQ-Si605 can show stronger aggregation ability and faster charge mobility as well as more efficient exciton dissociation in active layer as revealed by femtosecond transient absorption spectroscopy. With L8-BO-F as acceptor, its PMQ-Si605 based OSCs display power conversion efficiency (PCE) of 18.08%, much higher than 16.21% for PTQ11 based devices. With another acceptor BTP-H2 to optimize the photovoltaic performance of PMQ-Si605, further elevated PCEs of 18.50% and 19.15% can be achieved with the binary and ternary OSCs, respectively. Furthermore, PMQ-Si605 based active layers are suitable for processing in high humidity air, an important factor for massive production of OSCs. Therefore, the siloxane decoration on polymer donors is promising, affording PMQ-Si605 as a high-performing and low cost candidate.

15.
Mater Horiz ; 11(1): 283-296, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37943155

RESUMO

Enhancing the solution-processability of conjugated polymers (CPs) without diminishing their thin-film crystallinity is crucial for optimizing charge transport in organic field-effect transistors (OFETs). However, this presents a classic "Goldilocks zone" dilemma, as conventional solubility-tuning methods for CPs typically yield an inverse correlation between solubility and crystallinity. To address this fundamental issue, a straightforward skeletal randomization strategy is implemented to construct a quinoid-donor conjugated polymer, PA4T-Ra, that contains para-azaquinodimethane (p-AQM) and oligothiophenes as repeat units. A systematic study is conducted to contrast its properties against polymer homologues constructed following conventional solubility-tuning strategies. An unusually concurrent improvement of solubility and crystallinity is realized in the random polymer PA4T-Ra, which shows moderate polymer chain aggregation, the highest crystallinity and the least lattice disorder. Consequently, PA4T-Ra-based OFETs, fabricated under ambient air conditions, deliver an excellent hole mobility of 3.11 cm2 V-1 s-1, which is about 30 times higher than that of the other homologues and ranks among the highest for quinoidal CPs. These findings debunk the prevalent assumption that a random polymer backbone sequence results in decreased crystallinity. The considerable advantages of the skeletal randomization strategy illuminate new possibilities for the control of polymer aggregation and future design of high-performance CPs, potentially accelerating the development and commercialization of organic electronics.

16.
Adv Sci (Weinh) ; 11(25): e2401345, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38647436

RESUMO

The development of semiconducting polymers with good processability in green solvents and competitive electrical performance is essential for realizing sustainable large-scale manufacturing and commercialization of organic electronics. A major obstacle is the processability-performance dichotomy that is dictated by the lack of ideal building blocks with balanced polarity, solubility, electronic structures, and molecular conformation. Herein, through the integration of donor, quinoid and acceptor units, an unprecedented building block, namely TQBT, is introduced for constructing a serial of conjugated polymers. The TQBT, distinct in non-symmetric structure and high dipole moment, imparts enhanced solubility in anisole-a green solvent-to the polymer TQBT-T. Furthermore, PTQBT-T possess a highly rigid and planar backbone owing to the nearly coplanar geometry and quinoidal nature of TQBT, resulting in strong aggregation in solution and localized aggregates in film. Remarkably, PTQBT-T films spuncast from anisole exhibit a hole mobility of 2.30 cm2 V-1 s-1, which is record high for green solvent-processable semiconducting polymers via spin-coating, together with commendable operational and storage stability. The hybrid building block emerges as a pioneering electroactive unit, shedding light on future design strategies in high-performance semiconducting polymers compatible with green processing and marking a significant stride towards ecofriendly organic electronics.

17.
Phys Chem Chem Phys ; 15(18): 6856-63, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23545704

RESUMO

A conjugated copolymer based on alternating benzo[1,2-b;3,4-b']dithiophene (BDT) donor and dodecyloxy substituted benzo[c][1,2,5]thiadiazole (ABT) acceptor units was prepared for application in organic solar cells. A power conversion efficiency (PCE) of ~3% with a short-circuit current (Jsc) of 7.63 mA cm(-2), an open-circuit voltage (Voc) of 0.71 V and a fill-factor (FF) of 53.74% was obtained under the illumination of AM 1.5 solar irradiation (100 mW cm(-2)). Photovoltaic devices and their transient properties with a blend of the copolymer and the [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) at different ratios were studied using transient photovoltage (TPV), transient photocurrent (TPC) and atomic force microscopy (AFM) measurements. From the TPV and TPC measurements, the charge recombination times (τn) were found to be 21.1 µs, 12.6 µs and 10.5 µs, and the charge transport times (τd) were 1316 ns, 422 ns and 707 ns for the 1 : 0.5, 1 : 1 and 1 : 2 donor/acceptor (D/A) ratios, respectively. The 1 : 1 D/A ratio showed the shortest charge transport time (τd) and the longest charge diffusion length (Ln) according to L(n) [proportionality] √[τ(n)/τ(d)], leading to the highest device performance among the three ratios.

18.
Artigo em Inglês | MEDLINE | ID: mdl-37683359

RESUMO

The leopard coral grouper (Plectropomus leopardus) is a coral reef fish species that exhibits rapid and diverse color variation. However, the presence of melanoma and the high proportion of individuals displaying black color in artificial breeding have led to reduced economic and ornamental value. To pinpoint single nucleotide polymorphisms (SNPs) and potential genes linked to the black pigmentation characteristic in this particular species, This study gathered a cohort of 360 specimens from diverse origins and conducted a comprehensive genome-wide association analysis (GWAS) employing whole-genome resequencing. As a result, 57 SNPs related to the black skin trait were identified, and a grand total of 158 genes were annotated within 50 kb of these SNPs. Subsequently, GWAS was applied to three populations (LED, QHH, and QHL), and the corresponding results were compared with the analysis results of the total population. The results of the four GWAS models showed significant enrichment in Rap1 signaling pathway, melanin biosynthesis, metabolic pathways, tyrosine metabolism, cAMP signaling pathway, AMPK signaling pathway, PI3K-Akt signaling pathway, EGFR tyrosine kinase inhibitor resistance, HIF-1 signaling pathway, Ras signaling pathway, MAPK signaling pathway, etc. (p < 0.05), which were mainly associated with eleven genes (POL4, MET, E2F2, COMT, ZBED1, TYRP2, FOXP2, THIKA, LORF2, MYH16 and SOX2). Significant differences (p < 0.05) were observed in the expression of all 11 genes in the dorsal skin tissue, in 10 genes except COMT in the ventral skin tissue, and in all 11 genes in the caudal fin tissue. These findings imply that the control of body color in the P. leopardus is the result of the joint action of multiple genes and signaling pathways. These findings will contribute to a more profound comprehension of the genetic attributes that underlie the development of black skin in the vibrant P. leopardus, thus furnishing a theoretical foundation for genetic enhancement.


Assuntos
Antozoários , Bass , Humanos , Animais , Bass/genética , Estudo de Associação Genômica Ampla , Antozoários/genética , Fosfatidilinositol 3-Quinases/genética , Quênia , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética
19.
Adv Mater ; 35(39): e2302924, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37262926

RESUMO

Short-wavelength infrared (SWIR) organic light-emitting diodes (OLEDs) have attracted great interest due to their potential applications in biological imaging, infrared lighting, optical communication, environmental monitoring, and surveillance. Due to an intrinsic limitation posed by the energy-gap law, achieving high-brightness in SWIR OLEDs remains a challenge. Herein, the study reports the use of novel A-D-A'-D-A type small molecules NTQ and BTQ for high-performance SWIR OLEDs. Benefiting from multiple D-A effect in conjugated skeleton, the small molecules NTQ and BTQ exhibit narrow optical gaps of 1.23 and 1.13 eV, respectively. SWIR electroluminescence (EL) emission from OLEDs based on NTQ and BTQ is achieved, with emission peaks at 1140 and 1175 nm, respectively. Not only owing to a negligible efficiency roll-off across the full range of applied current density but also the ability to afford a high operation current density of 5200 mA cm-2 , the resultant SWIR OLEDs based on NTQ exhibit a maximal radiant exitance of =1.12 mW cm-2 . Furthermore, the NTQ-based OLEDs also possess sub-gap turn-on voltage of 0.85 V, which is close to the physical limits derived from the generalized Kirchhoff and Planck equation. This work demonstrates that A-D-A'-D-A type small molecules offer significant promise for NIR/SWIR emitting material innovations.

20.
ChemSusChem ; 15(15): e202200789, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35606681

RESUMO

Side-chain engineering has been proved to show profound impact on polymer properties and blend morphology. Herein, the critical role of siloxane-terminated alkoxy side chains was revealed by a tiny decorating method through which the molar content of siloxane-terminated alkoxy side chain was fixed to 5 %, and its alkyl linker was the only tuning factor. The pentylene, heptylene, and nonylene linkers were designed and used to synthesize wide-bandgap polymers PQSi505, PQSi705, and PQSi905, respectively. Interestingly, the siloxane pendant of combinatory side chain exhibited a distinct impact on molecular packing when its branching position shifted slightly. Among the three polymers, PQSi705 had the strongest aggregation and the highest packing order. Finally, toluene-processed organic solar cells (OSCs) based on PQSi705 and Y6-BO achieved the best power conversion efficiency of 15.77 %. This work suggests that siloxane pendant can serve as a powerful modulator to enhance the photovoltaic performance of OSCs.

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