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1.
Angew Chem Int Ed Engl ; : e202411512, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38988004

RESUMEN

Overcoming the trade-off between short-circuited current (Jsc) and open-circuited voltage (Voc) is important to achieving high-efficiency organic solar cells (OSCs). Previous works modulated energy gap between Frenkel local exciton (LE) and charge-transfer (CT) exciton, which is served as driving force of exciton splitting. Differently, our current work focuses on modulation of LE-CT excitonic coupling (tLE-CT) via a simple but effective strategy that the 2-chlorothiophene (2Cl-Th) solvent is utilized in treatment of OSC active-layer films. The results of our experimental measurements and theoretical simulations demonstrated that 2Cl-Th solvent initiates the tighter intermolecular interactions with non-fullerene acceptor in comparison with that of traditional chlorobenzene solvent, thus suppressing the acceptor's over-aggregation and retarding the acceptor crystallization with reduced trap. Importantly, the resulted shorter distances between donor and acceptor molecules in the 2Cl-Th treated blend efficiently strengthen tLE-CT, which not only promotes the exciton splitting but also reduces non-radiative recombination. The champion efficiencies of 19.8% (small-area) with a superior operational reliability (T80: 586 hours) and 17.0% (large-area) were yielded in 2Cl-Th treated cells. This work provided a new insight into modulating the exciton dynamics to overcome the trade-off between Jsc and Voc, which can productively promote the development of OSC field.

3.
Plant Commun ; : 101000, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38859586

RESUMEN

Hybrid crops often exhibit increased yield and greater resilience, yet the genomic mechanism(s) underlying hybrid vigor or heterosis remain unclear, hindering our ability to predict the expression of phenotypic traits in hybrid breeding. Here, we generated haplotype-resolved T2T genome assemblies of two pear hybrid varieties, 'Yuluxiang' (YLX) and 'Hongxiangsu' (HXS), which share the same maternal parent but differ in their paternal parents. We then used these assemblies to explore the genome-scale landscape of allele-specific expression (ASE) and create a pangenome graph for pear. ASE was observed for close to 6000 genes in both hybrid cultivars. A subset of ASE genes related to aspects of fruit quality such as sugars, organic acids, and cuticular wax were identified, suggesting their important contributions to heterosis. Specifically, Ma1, a gene regulating fruit acidity, is absent in the paternal haplotypes of HXS and YLX. A pangenome graph was built based on our assemblies and seven published pear genomes. Resequencing data for 139 cultivated pear genotypes (including 97 genotypes sequenced here) were subsequently aligned to the pangenome graph, revealing numerous structural variant hotspots and selective sweeps during pear diversification. As predicted, the Ma1 allele was found to be absent in varieties with low organic acid content, and this association was functionally validated by Ma1 overexpression in pear fruit and calli. Overall, these results reveal the contributions of ASE to fruit-quality heterosis and provide a robust pangenome reference for high-resolution allele discovery and association mapping.

4.
Nanomicro Lett ; 16(1): 224, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888701

RESUMEN

Organic photovoltaics (OPVs) need to overcome limitations such as insufficient thermal stability to be commercialized. The reported approaches to improve stability either rely on the development of new materials or on tailoring the donor/acceptor morphology, however, exhibiting limited applicability. Therefore, it is timely to develop an easy method to enhance thermal stability without having to develop new donor/acceptor materials or donor-acceptor compatibilizers, or by introducing another third component. Herein, a unique approach is presented, based on constructing a polymer fiber rigid network with a high glass transition temperature (Tg) to impede the movement of acceptor and donor molecules, to immobilize the active layer morphology, and thereby to improve thermal stability. A high-Tg one-dimensional aramid nanofiber (ANF) is utilized for network construction. Inverted OPVs with ANF network yield superior thermal stability compared to the ANF-free counterpart. The ANF network-incorporated active layer demonstrates significantly more stable morphology than the ANF-free counterpart, thereby leaving fundamental processes such as charge separation, transport, and collection, determining the device efficiency, largely unaltered. This strategy is also successfully applied to other photovoltaic systems. The strategy of incorporating a polymer fiber rigid network with high Tg offers a distinct perspective addressing the challenge of thermal instability with simplicity and universality.

5.
Angew Chem Int Ed Engl ; : e202407355, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837587

RESUMEN

The structure of molecular aggregates is crucial for charge transport and photovoltaic performance in organic solar cells (OSCs). Herein, the intermolecular interactions and aggregated structures of nonfused-ring electron acceptors (NFREAs) are precisely regulated through a halogen transposition strategy, resulting in a noteworthy transformation from a 2D-layered structure to a 3D-interconnected packing network. Based on the 3D electron transport pathway, the binary and ternary devices deliver outstanding power conversion efficiencies (PCEs) of 17.46 % and 18.24 %, respectively, marking the highest value for NFREA-based OSCs.

6.
Adv Mater ; : e2402833, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38837820

RESUMEN

Leveraging breakthroughs in Y-series nonfullerene acceptors (NFAs), organic solar cells (OSCs) have achieved impressive power conversion efficiencies (PCEs) exceeding 19%. However, progress in advancing OSCs has decelerated due to constraints in realizing the full potential of the Y-series NFAs. Herein, a simple yet effective solid additive-induced preaggregation control method employing 2-chloro-5-iodopyridine (PDCI) is reported to unlock the full potential of the Y-series NFAs. Specifically, PDCI interacts predominantly with Y-series NFAs enabling enhanced and ordered phase-aggregation in solution. This method leads to a notable improvement and a redshifted absorption of the acceptor phase during film formation, along with improved crystallinity. Moreover, the PDCI-induced preaggregation of NFAs in the solution enables ordered molecule packing during the film-formation process through delicate intermediate states transition. Consequently, the PDCI-induced preaggregated significantly improves the PCE of PM6:Y6 OSCs from 16.12% to 18.12%, among the best values reported for PM6:Y6 OSCs. Importantly, this approach is universally applicable to other Y-series NFA-based OSCs, achieving a champion PCE of 19.02% for the PM6:BTP-eC9 system. Thus, the preaggregation control strategy further unlocks the potential of Y-series NFAs, offering a promising avenue for enhancing the photovoltaic performance of Y-series NFA-based OSCs.

7.
Sci Rep ; 14(1): 10173, 2024 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702351

RESUMEN

This study aimed to explore the changes of pharmacokinetic parameters after meropenem in patients with abdominal septic shock after gastrointestinal perforation, and to simulate the probability of different dosing regimens achieving different pharmacodynamic goals. The study included 12 patients, and utilized high performance liquid chromatography-tandem mass spectrometry to monitor the plasma concentration of meropenem. The probability of target attainment (PTA) for different minimum inhibitory concentration (MIC) values and %fT > 4MIC was compared among simulated dosing regimens. The results showed that in 96 blood samples from 12 patients, the clearance (CL) of meropenem in the normal and abnormal creatinine clearance subgroups were 7.7 ± 1.8 and 4.4 ± 1.1 L/h, respectively, and the apparent volume of distribution (Vd) was 22.6 ± 5.1 and 17.2 ± 5.8 L, respectively. 2. Regardless of the subgroup, 0.5 g/q6h infusion over 6 h regimen achieved a PTA > 90% when MIC ≤ 0.5 mg/L. 1.0 g/q6h infusion regimen compared with other regimen, in most cases, the probability of making PTA > 90% is higher. For patients at low MIC, 0.5 g/q6h infusion over 6 h may be preferable. For patients at high MIC, a dose regimen of 1.0 g/q6 h infusion over 6 h may be preferable. Further research is needed to confirm this exploratory result.


Asunto(s)
Antibacterianos , Meropenem , Pruebas de Sensibilidad Microbiana , Choque Séptico , Humanos , Meropenem/farmacocinética , Meropenem/administración & dosificación , Meropenem/uso terapéutico , Choque Séptico/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Prospectivos , Antibacterianos/farmacocinética , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Adulto , Perforación Intestinal , Anciano de 80 o más Años
8.
Chem Commun (Camb) ; 60(46): 5980-5983, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38769815

RESUMEN

Tuning the electrode-molecule interface stands at the heart of functional single-molecule devices. Herein, we report that the electrode-molecule interface of difluoro-substituted benzothiadiazole (FBTZ)-based single-molecule junctions can be modulated by the bias voltage. At low bias voltage (100 mV), the dative Au-N linkage is formed and at high bias voltage (600 mV), a covalent Au-C linkage is constructed. These junctions show distinct conductance. Interestingly, dominant charge carriers in Au-N- and Au-C-based junctions are different, as evidenced by dft calculations. These results provide a new strategy for regulating the electrode-molecule interface, which will advance the development of molecular electronics.

9.
Adv Sci (Weinh) ; 11(25): e2401952, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38647398

RESUMEN

The general strategy for n-type organic thermoelectric is to blend n-type conjugated polymer hosts with small molecule dopants. In this work, all-polymer n-type thermoelectric is reported by dissolving a novel n-type conjugated polymer and a polymer dopant, poly(ethyleneimine) (PEI), in alcohol solution, followed by spin-coating to give polymer host/polymer dopant blend film. To this end, an alcohol-soluble n-type conjugated polymer is developed by attaching polar and branched oligo (ethylene glycol) (OEG) side chains to a cyano-substituted poly(thiophene-alt-co-thiazole) main chain. The main chain results in the n-type property and the OEG side chain leads to the solubility in hexafluorineisopropanol (HFIP). In the polymer host/polymer dopant blend film, the Coulombic interaction between the dopant counterions and the negatively charged polymer chains is reduced and the ordered stacking of the polymer host is preserved. As a result, the polymer host/polymer dopant blend exhibits the power factor of 36.9 µW m-1 K-1, which is one time higher than that of the control polymer host/small molecule dopant blend. Moreover, the polymer host/polymer dopant blend shows much better thermal stability than the control polymer host/small molecule dopant blend. This research demonstrates the high performance and excellent stability of all-polymer n-type thermoelectric.

10.
Angew Chem Int Ed Engl ; : e202403068, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687308

RESUMEN

Organic self-assembled molecules (OSAMs) based hole-transporting materials play a pivotal role in achieving highly efficient and stable inverted perovskite solar cells (IPSCs). However, the reported carbazol-based OSAMs have serious drawbacks, such as poor wettability for perovskite solution spreading due to the nonpolar surface, worse matched energy arrangement with perovskite, and limited molecular species, which greatly limit the device performance. To address above problems, a novel OSAM [4-(3,6-glycol monomethyl ether-9H-carbazol-9-yl) butyl]phosphonic acid (GM-4PACz) was synthesized as hole-transporting material by introducing glycol monomethyl ether (GM) side chains at carbazolyl unit. GM groups enhance the surface energy of Indium Tin Oxide (ITO)/SAM substrate to facilitate the nucleation and growth of up perovskite film, suppress cation defects, release the residual stress at SAM/perovskite interface, and evaluate energy level for matching with perovskite. Consequently, the GM-4PACz based IPSC achieves a champion PCE of 25.52 %, a respectable open-circuit voltage (VOC) of 1.21 V, a high stability, possessing 93.29 % and 91.75 % of their initial efficiency after aging in air for 2000 h or tracking at maximum power point for 1000 h, respectively.

11.
bioRxiv ; 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38645120

RESUMEN

Motivation: RNA-Seq data analysis is commonly biased towards detecting differentially expressed genes and insufficiently conveys the complexity of gene expression changes between biological conditions. This bias arises because discrete models of RNA-Seq count data cannot fully characterize the mean, variance, and skewness of gene expression distribution using independent model parameters. A unified framework that simultaneously tests for differential expression, variability, and skewness is needed to realize the full potential of RNA-Seq data analysis in a systems biology context. Results: We present SIEVE, a statistical methodology that provides the desired unified framework. SIEVE embraces a compositional data analysis framework that transforms discrete RNA-Seq counts to a continuous form with a distribution that is well-fitted by a skew-normal distribution. Simulation results show that SIEVE controls the false discovery rate and probability of Type II error better than existing methods for differential expression analysis. Analysis of the Mayo RNA-Seq dataset for Alzheimer's disease using SIEVE reveals that a gene set with significant expression difference in mean, standard deviation and skewness between the control and the Alzheimer's disease group strongly predicts a subject's disease state. Furthermore, functional enrichment analysis shows that relying solely on differentially expressed genes detects only a segment of a much broader spectrum of biological aspects associated with Alzheimer's disease. The latter aspects can only be revealed using genes that show differential variability and skewness. Thus, SIEVE enables fresh perspectives for understanding the intricate changes in gene expression that occur in complex diseases. Availability: The SIEVE R package and source codes are available at https://github.com/Divo-Lee/SIEVE .

12.
Adv Mater ; 36(21): e2310711, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38528777

RESUMEN

Developing an additive to effectively regulate the perovskite crystallization kinetics for the optimized optoelectronic properties of perovskite film plays a vital role in obtaining high efficiency and stable perovskite solar cells (PSCs). Herein, a new additive is designed and directly synthesized in perovskite precursor solution by utilizing an addition reaction between but-3-yn-1-amine hydrochloride (BAH) and formamidinium iodide. It is found that its product may control the intermediate precursor phase for regulating perovskite nucleation, leading to advantageous 2D perovskite to induce growth of perovskite along the preferred [001] orientation with not only released lattice strain but also strong interaction with perovskite to passivate its surface defects. By taking advantage of the above synergistic effects, the optimized PSC delivers an efficiency of 25.19% and a high open-circuit voltage (VOC) of 1.22 V. Additionally, the devices demonstrate good stability, remaining over 90% of their initial efficiencies under ambient atmosphere conditions for 60 days, high temperature of 85 °C for 200 h, or maximum power point tracking for 500 h.

13.
Adv Mater ; 36(25): e2400521, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38477468

RESUMEN

Large-area printing fabrication is a distinctive feature of organic solar cells (OSCs). However, the advance of upscalable fabrication is challenged by the thickness of organic active layers considering the importance of both exciton dissociation and charge collection. In this work, a bulk-heterojunction-buried (buried-BHJ) structure is introduced by sequential deposition to realize efficient exciton dissociation and charge collection, thereby contributing to efficient OSCs with 500 nm thick active layers. The buried-BHJ distributes donor and acceptor phases in the vertical direction as charge transport channels, while numerous BHJ interfaces are buried in each phase to facilitate exciton dissociation simultaneously. It is found that buried-BHJ configurations possess efficient exciton dissociation and rapid charge transport, resulting in reduced recombination losses. In comparison with traditional structures, the buried-BHJ structure displays a decent tolerance to film thickness. In particular, a power conversion efficiency of 16.0% is achieved with active layers at a thickness of 500 nm. To the best of the authors' knowledge, this represents the champion efficiency of thick film OSCs.

14.
Nat Commun ; 15(1): 1946, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38431627

RESUMEN

All-small-molecule organic solar cells with good batch-to-batch reproducibility combined with non-halogen solvent processing show great potential for commercialization. However, non-halogen solvent processing of all-small-molecule organic solar cells are rarely reported and its power conversion efficiencies are very difficult to improve. Herein, we designed and synthesized a small molecule donor BM-ClEH that can take advantage of strong aggregation property induced by intramolecular chlorine-sulfur non-covalent interaction to improve molecular pre-aggregation in tetrahydrofuran and corresponding micromorphology after film formation. Tetrahydrofuran-fabricated all-small-molecule organic solar cells based on BM-ClEH:BO-4Cl achieved high power conversion efficiencies of 15.0% in binary device and 16.1% in ternary device under thermal annealing treatment. In contrast, weakly aggregated BM-HEH without chlorine-sulfur non-covalent bond is almost inefficient under same processing conditions due to poor pre-aggregation induced disordered π-π stacking, indistinct phase separation and exciton dissociation. This work promotes the development of non-halogen solvent processing of all-small-molecule organic solar cells and provides further guidance.

15.
Quant Imaging Med Surg ; 14(3): 2345-2356, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38545062

RESUMEN

Background: Conventional computed tomography (CT) has low sensitivity for the diagnosis of bone marrow infiltration in nonosteolytic multiple myeloma (NOL-MM). This study aimed to compare the performance of the two-material decomposition technique of spectral CT with the removal of X-ray absorption components of calcium (Ca) versus that of hydroxyapatite (HAP) for diagnosis of NOL-MM. Methods: From October 2022 to March 2023, a total of 41 consecutive patients with MM without focal bone lesions undergoing chest spectral CT and thoracic spine magnetic resonance imaging (MRI) in Fujian Medical University Union Hospital were prospectively enrolled; meanwhile, another set of 41 age- and sex-matched healthy consecutive participants were selected as a comparison group. Based on MRI findings, patients with MM were classified with a diffuse infiltration pattern MM (DP-MM) or a normal pattern MM (NP-MM). Regions of interest (ROIs) were manually drawn on vertebrae. CT values of 70-keV images and basic material density within the ROIs were stored. The basic two-material pairs included a Ca-related pair (Ca-X) and an HAP-related pair (HAP-X), with X referring to fat, water, or muscle. Material density values DCa(X), DX(Ca), DHAP(X), and DX(HAP) were each used to diagnose MM, and the area under the receiver operating characteristic curve (AUC) was used to assess diagnostic performance. Results: The 41 patients with NOL-MM included 30 with DP-MM and 11 with NP-MM. CT value, DCa(X), and DHAP(X) were comparable between the NOL-MM, DP-MM, NP-MM, and comparison groups. DX(HAP) was better than DX(Ca) for distinguishing the NOL-MM group from the comparison group {AUC [95% confidence interval (CI)], 0.874 (0.800, 0.949) vs. 0.737 (0.630, 0.844); P=0.02}, the DP-MM group from the comparison group [AUC (95% CI), 0.933 (0.878, 0.989) vs. 0.785 (0.677, 0.894); P=0.01], the NP-MM group from the comparison group [AUC (95% CI), 0.714 (0.540, 0.888) vs. 0.605 (0.429, 0.782); P=0.03], and the DP-MM group from the NP-MM group [AUC (95% CI), 0.809 (0.654, 0.964) vs. 0.736 (0.566, 0.907); P=0.049]. The diagnostic performance of DX(HAP) and DX(Ca) was influenced only by the removed material, while the X material had no influence. Conclusions: The spectral CT two-material decomposition technique with removal of X-ray absorption components of HAP is useful for diagnosis of NOL-MM, irrespective of the paired material.

16.
ACS Appl Mater Interfaces ; 16(12): 15426-15434, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38497376

RESUMEN

High-conducting single-molecule junctions have attracted a great deal of attention, but insulating single-molecule junctions, which are critical in molecular circuits, have been less investigated due to the long-standing challenges. Herein, the in situ formation of a Au-C linker via electrical-potential-mediated sp2 C-H bond metalation of polyfluoroarenes with the assistance of scanning tunneling microscope-based break junction technique is reported. This metalation process is bias-dependent and occurs with an electropositive electrode, and the formed junction is highly oriented. Surprisingly, these polyfluoroarenes exhibit unexpected low conductance even under short molecular lengths and are superior molecular insulators. Flicker noise analysis and DFT calculations confirm that the insulating properties of polyfluoroarenes are ascribed to their multiple fluorine substituents. Our results pave a way for constructing oriented asymmetric molecular junctions and provide an efficient strategy to suppress the single-molecule conductance, which will aid in the design of molecular insulators and advance the development of self-integrating functional molecular circuits.

17.
Materials (Basel) ; 17(6)2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38541422

RESUMEN

Al-based foams have drawn increasing attention from industry due to their integration of structure and functional properties. However, large-sized Al-based foams still cannot be homogeneously strengthened by long-time aging due to their low thermal conductivity. In this study, we proposed an age-hardening approach that was applied in large-sized Al-0.16Sc-0.17Zr (wt.%) foams via micro-alloying with Zr and Ti compared with Al-0.21Sc foams; it not only achieved homogeneous strength by long-term aging but also reduced the cost of the alloy by substituting Zr and Ti for the more expensive Sc content. The results show that the Al3(Sc, Zr, Ti) phase with a core-shell structure as a crucial precipitation strengthening phase by micro-alloying with Zr and Ti was less prone to coarsening after a prolonged aging heat treatment. Therefore, the yielding strength of Al-Sc foam micro-alloying with Zr and Ti remained almost unchanged after a maximum aging time of 1440 h due to less coarsening precipitate, which is consistent with the results of mechanical experiments. These findings provide a new way for the heat treatment strengthening of large-sized Al-based foams, thus promoting their industrial applications.

18.
Molecules ; 29(6)2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38542969

RESUMEN

Although much promising synthetic progress in conjugated polymer-based organic solar cells (OSCs) has resulted in significant improvement in power conversion efficiencies (PCEs) of from over 15 to >19.0% in the last five years, the sophisticated and complex reactions from at least two families' monomers with remarkably different electron push-pull effects could still pose an unavoidable material burden for the commercialization of OSCs in the coming future. Therefore, the method of preparing a homopolymer from a sole monomer would significantly reduce the synthetic steps and costs in order to pave the way for the large-scale production of OSC materials. Therefore, alkylthio-thiophenyl-substituted benzo[1,2-b;4,5-b']dithiophene (BDTTS) as the sole and key structural moiety with dihalogen and distannyl functional groups was designed and synthesized, respectively, in this study, for facile monomer syntheses and polymerizations to achieve three wide-bandgap homopolymer donors of BDTTS-alt-BDTT-Cl (P13), BDTTS-alt-BDTT (P15), and BDTTS (P14), respectively. The structural symmetry dependency on their physical, electrochemical, and optical properties, thin-film morphologies, and photovoltaic (PV) performance was investigated in detail. As a result, OSCs based on the asymmetric polymer P15, paired with BTP-eC9 as the electron acceptor, presented the best PV performance, with a PCE of 11.5%, a fill factor (FF) of 65.87%, and a short-circuit current (JSC) of 22.04 mA·cm-2, respectively. This PCE value is among the highest ones reported for BDT-type homopolymer donor-based OPVs, providing us with knowledge for obtaining promising PV performance from devices made of P15-like materials.

20.
Adv Mater ; 36(15): e2304632, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37418757

RESUMEN

Using two structurally similar polymer acceptors in constructing high-efficiency ternary all-polymer solar cells is a widely acknowledged strategy; however, the focus thus far has not been on how polymer acceptor(s) would tune the aggregation of polymer donors, and furthermore film morphology and device performance (efficiency and stability). Herein, it is reported that matching of the celebrity acceptor PY-IT and the donor PBQx-TCl results in enhanced H-aggregation in PBQx-TCl, which can be finely tuned by controlling the amount of the second acceptor PY-IV. Consequently, the efficiency-optimized PY-IV weight ratio (0.2/1.2) leads to a state-of-the-art power conversion efficiency of 18.81%, wherein light-illuminated operational stability is also enhanced along with well-protected thermal stability. Such enhancements in the efficiency and operational and thermal stabilities of solar cells can be attributed to morphology optimization and the desired glass transition temperature of the target active layer based on comprehensive characterization. In addition to being a high-power conversion efficiency case for all-polymer solar cells, these enhancements are also a successful attempt for using combined acceptors to tune donor aggregation toward optimal morphology, which provides a theoretical basis for the construction of other types of organic photovoltaics beyond all-polymer solar cells.

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