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A series of dual-band photomultiplication (PM)-type organic photodetectors (OPDs) were fabricated by employing a donor(s)/acceptor (100:1, wt/wt) mixed layer and an ultrathin Y6 layer as the active layers, as well as by using PNDIT-F3N as an interfacial layer near the indium tin oxide (ITO) electrode. The dual-band PM-type OPDs exhibit the response range of 330–650 nm under forward bias and the response range of 650–850 nm under reverse bias. The tunable spectral response range of dual-band PM-type OPDs under forward or reverse bias can be explained well from the trapped electron distribution near the electrodes. The dark current density (JD) of the dual-band PM-type OPDs can be efficiently suppressed by employing PNDIT-F3N as the anode interfacial layer and the special active layers with hole-only transport characteristics. The light current density (JL) of the dual-band PM-type OPDs can be slightly increased by incorporating wide-bandgap polymer P-TPDs with relatively large hole mobility (μh) in the active layers. The signal-to-noise ratios of the optimized dual-band PM-type OPDs reach 100,980 under −50 V bias and white light illumination with an intensity of 1.0 mW·cm–2, benefiting from the ultralow JDby employing wide-bandgap PNDIT-F3N as the anode interfacial buffer layer and the increased JLby incorporating appropriate P-TPD in the active layers.

Perovskite light-emitting diodes (PeLEDs) based on CsPb(Br/I)3nanocrystals (NCs) usually suffer from severe spectral instability under operating voltage due to the poor-quality PeNCs. Herein, zeolite was utilized to prepare high-quality CsPb(Br/I)3NCs via promoting the homogeneous nucleation and growth and suppressing the Ostwald ripening of PeNCs. In addition, the decomposed zeolite interacted strongly with PeNCs through Pb–O bonds and hydrogen bonds, which inhibited the formation of defects and suppressed halide ion migration, leading to an improved photoluminescence quantum yield (PLQY) and enhanced stability of PeNCs. Moreover, the strong binding affinity of decomposed zeolite to PeNCs contributed to the formation of homogeneous perovskite films with high PLQY. As a result, pure-red PeLEDs with Commission International de I’Eclairage (CIE) coordinates of (0.705, 0.291) were fabricated, approaching the Rec. 2020 red primary color. The devices achieved a peak external quantum efficiency of 23.0% and outstanding spectral stability.

While quasi-two-dimensional (quasi-2D) perovskites have good properties of cascade energy transfer, high exciton binding energy, and high quantum efficiency, which will benefit high-efficiency blue PeLEDs, inefficient domain distribution management and unbalanced carrier transport impede device performance improvement. Herein, (2-(9H-carbazol-9-yl)ethyl)phosphonic acid (2PACz) and methyl 2-aminopyridine-4-carboxylate (MAC) were simultaneously introduced to a blue quasi-2D perovskite film. Relying on the synergistic effect of 2PACz and MAC, it not only modulates the phase distribution inhibiting the n= 2 phase but also greatly improves the electrical property of the quasi-2D perovskite film. As a result, the as-modified blue quasi-2D PeLED demonstrated an external quantum efficiency (EQE) of 17.08% and a luminance of 10142 cd m–2. This study exemplifies the synergistic effect among dual additives and offers a new effective additive strategy modulating phase distribution and building balanced carrier transport, which paves the way for the fabrication of highly efficient blue PeLEDs.

Lanthanide-based nanomaterials have been extensively studied, owing to their unique optical properties. Strong electron coupling intensely affects the optical properties, as a kind of interaction between the metal luminescence centers, which usually depend on the otherness in valence states and/or spin states of metal ions. Herein, we presented that the strong electron coupling between trivalent lanthanide ions (LnIII) existed in molecular cluster-aggregates (MCAs) beyond the general consideration in valence and/or spin states. We synthesized a series of lanthanide-based MCAs with the generalized formula [Ln20(chp)30(CO3)12(NO3)6(H2O)6]({Ln20}). By comparing and analyzing the characteristics of homometallic and heterometallic {Ln20}MCAs, we found a regular and controlled phenomenon of metal-to-metal charge transfer (MMCT) which is a typical expression of strong electron coupling. This observation can be attributed to the shorter spacing between metals inside the polynuclear nanosized core of MCAs, indicating that MCAs are an excellent matrix material to study the effects of intermetallic interactions of LnIII, thus tailoring even customization in their luminescence performance.

To address the issue of increased shifting shocks caused by the limitations of the engine's full-speed regulation (FSR) characteristics during upshifting in heavy-duty vehicles, this paper proposes a coordinated control multi-objective optimisation strategy for reducing shifting shocks. This strategy takes into account the transient characteristics of the engine during the shifting process and uses long short-term memory (LSTM) neural networks to establish a reduced-order engine model. Based on the influence of the transient characteristics of the engine on shifting shock, a coordinated control scheme is formulated. To obtain the optimal solution for control parameters, a multi-objective optimisation was performed using the nondominated sorting genetic algorithm-II (NSGA-II) algorithm with the minimisation of root mean square of shifting shocks and friction work as optimisation objectives. Finally, the proposed coordinated control strategy was verified through simulation comparisons, demonstrating its superior control effectiveness in significantly reducing shifting shocks.

TiO2is a sintering additive that can significantly improve the sintering and mechanical properties of Cr2O3–Al2O3refractory materials with high Cr2O3contents. In this study, TiO2-reinforced Cr2O3–Al2O3composite refractories were prepared using a reaction-sintering process. The microstructure, phase composition, mechanical properties, and strengthening mechanism of the TiO2-reinforced Cr2O3–Al2O3composite refractories were investigated. The results indicated that the Al2O3–Cr2O3–TiO2composite refractory with a TiO2content of 3.0–4.5 wt% had good compactness (porosity of 5.89%), hardness (17.21 GPa), wear resistance (wear rate of 0.4 mm3/Nm), flexural strength (101.10 MPa), and compressive strength (420.90 MPa). This is mainly because when the added amount of TiO2was <3.0 wt%, TiO2was solidly soluble in the matrix, forming a Ti3+-doped (Cr, Al)2O3solid solution, inhibiting abnormal grain growth, rapidly increasing the sintering shrinkage of the sample, rapidly increasing the bulk density, rapidly decreasing the apparent porosity, and improving the sintering and mechanical properties of the composite resistant material. When the TiO2addition exceeded 4.5 wt%, a large amount of (Cr, Al)2TiO5phase was distributed between the grain boundaries of the solid solution, and its bulk density started to decrease. The sintering shrinkage and apparent porosity did not change significantly, and the bonding between the solid solution was not improved. Thus, the sintering and mechanical properties of the composite resistant material deteriorated. Taking into account the slag resistance and mechanical properties of the material, Al2O3–Cr2O3–TiO2with a TiO2content of 3.0–4.5 wt% can meet the service requirements for mechanical properties of the lining of smelting reduction ironmaking furnaces.

Malignant tumors are major causes of morbidity and mortality in China. Despite advances in surgical, radiological, chemotherapeutic, molecular targeting, and immunotherapeutic treatments, patients with malignant tumors still have poor prognoses. Low-dose-rate brachytherapy, specifically 125I seed implantation, is beneficial because of its high local delivery dose and minimal damage to surrounding tissues. Consequently, it has gained increasing acceptance as a treatment modality for various malignant tumors. In this study, we explored the fundamental principles, clinical applications, and new technologies associated with 125I radioactive seed implantation.

The multifunctional bottom-up double-layer optimization strategy is developed to simultaneously passivate bulk defects and interface defects of PSCs. The λ-C-modified PSCs demonstrate high PCE with 23.81%, and highly environmental stability.

In this work, layer-by-layer (LbL) polymer solar cells (PSCs) are constructed without/with the incorporation of a dissociation strengthening layer (DSL) on the basis of the wide-bandgap donor D18-Cl, as well as the narrow-bandgap nonfullerene acceptor Y6. The efficiency of LbL PSCs is enhanced from 17.62 to 18.15% through introducing a DSL, originating from the enhanced dissociation of D18-Cl excitons near the ITO electrode. Meanwhile, the interfacial energy between D18-Cl and Y6 layers is decreased by incorporating a DSL, which should facilitate molecular interdiffusion for more adequate exciton dissociation in LbL active layers. This work offers a simple and resultful way for realizing power conversion efficiency (PCE) improvement of LbL PSCs with maximized exciton utilization in LbL active layers. The universality of the DSL incorporation strategy on performance improvement can be further confirmed with a boosted PCE from 17.39 to 18.03% or from 17.13 to 17.61% for D18-Cl/L8-BO- or D18-Cl/N3-based LbL PSCs by incorporating a DSL.

Cesium lead halide perovskite nanocrystals (PNCs) exhibit promising prospects for application in optoelectronic devices. However, electroactivated near-infrared (NIR) PNC light-emitting diodes (LEDs) with emission peaks over 800 nm have not been achieved. Herein, we demonstrate the electroactivated NIR PNC LEDs based on Yb3+-doped CsPb(Cl1–xBrx)3PNCs with extraordinary high NIR photoluminescence quantum yields over 170%. The fabricated NIR LEDs possess an irradiance of 584.7 μW cm–2, an EQE of 1.2%, and a turn-on voltage of 3.1 V. The ultrafast quantum cutting process from the PNC host to Yb3+has been revealed as the main mechanism of electroluminescence (EL)-activated Yb3+for the first time via exploring how the trend between the EL intensity of PNC and Yb3+varies with different voltages along with the tendency of temperature- and doping-concentration-dependent PL and EL spectra. This work will extend the application of PNCs to optical communication, night-vision devices, and biomedical imaging.

Besides entity-centric knowledge, usually organized as Knowledge Graph (KG), events are also an essential kind of knowledge in the world, which trigger the spring up of event-centric knowledge representation form like Event KG (EKG). It plays an increasingly important role in many downstream applications, such as search, question-answering, recommendation, financial quantitative investments, and text generation. This paper provides a comprehensive survey of EKG from history, ontology, instance, and application views. Specifically, to characterize EKG thoroughly, we focus on its history, definition, schema induction, acquisition, related representative graphs/systems, and applications. The development processes and trends are studied therein. We further summarize prospective directions to facilitate future research on EKG.

Broadband photomultiplication-type organic photodetectors (PM-OPDs) were prepared with PMBBDT:PY3Se-2V (1:1, wt/wt) as the absorbing layer (AL) and PC71BM:P3HT (100:5, wt/wt) as the photomultiplication layer (PML) on the basis of the sandwich structure. The incident photons from ultraviolet light to the near-infrared region can be harvested by AL. The rather less P3HT in PML can produce plenty of isolated hole traps with P3HT surrounded by PC71BM; the electron tunneling injection induced by trapped holes near the Ag electrode can lead to the photomultiplication (PM) phenomenon. The performance of PM-OPDs can be effectively improved by optimizing the AL thickness. The optimal PM-OPDs exhibit a broad spectral response from 300 to 1050 nm as well as an external quantum efficiency (EQE) of 5800% at 340 nm at 10 V bias, along with a specific detectivity (D*) of 3.78 × 1013Jones. The spectral response of PM-OPDs is controlled by the trapped-hole distribution near the Ag electrode, primarily originating from the photogenerated holes in AL. To further optimize the spectral response of PM-OPDs, the optical filter layer (OFL) was used to manipulate light field distribution in AL. The violet, red, and near-infrared-light PM-OPDs were developed by employing different OFLs.

Photomultiplication-type polymer photodetectors (PM-PPDs) were achieved with polymer P3HT as donor and PY3Se-1V as acceptor based on structure of ITO/PEDOT:PSS/active layer/Al. The optimal weight ratio of P3HT to PY3Se-1V is about 100:3. Amounts of isolated electron traps are formed with PY3Se-1V surrounded by P3HT due to rather less content of PY3Se-1V in active layers and about 0.94 eV energy offset between the lowest unoccupied molecular orbitals (LUMO) of P3HT and PY3Se-1V. The optimal PM-PPDs exhibit broad spectral response from 350 to 950 nm and external quantum efficiency (EQE) values of 68,200% at 360 nm, 26,400% at 630 nm and 19,500% at 850 nm under −15 V bias. The working mechanism of PM-PPDs is attributed to the interfacial trap-assisted hole tunneling injection from external circuit. The performance of PM-PPDs can be further improved by incorporating appropriate PMBBDT with high hole mobility as the third component. The EQE values of optimal ternary PM-PPDs are increased to 105,000% at 360 nm, 40,000% at 630 nm and 31,800% at 850 nm under −15 V bias, benefiting from the enhanced hole transport in ternary active layers. The optimal ternary PM-PPDs were successfully applied in a light-controlled circuit to turn on or turn off light emitting diode (LED).

The emerging polymerized small-molecule acceptors (PSMAs) with near-infrared (NIR) absorption have not only significantly boosted the power conversion efficiencies (PCEs) of all-polymer solar cells (all-PSCs) but have also exhibited great potential for sensitive NIR polymeric photodetectors (PPDs). However, there is no report regarding PSMAs with photo-response that can approach 1000 nm, which is an important criterion for applications in NIR-responsive all-PSCs and PPDs. Herein, by unidirectionally inserting vinylene segments into a selenophene-rich polymer backbone to improve the electron-donating strength and quinoidal character, an asymmetric PSMA, namely, PY3Se-1V, was developed, which showed an extensively red-shifted absorption approaching 1000 nm. The PBDB-T:PY3Se-1V-based binary all-PSCs achieve a decent PCE of 13.2% and a record-high photocurrent density of 25.9 mA cm–2due to the significantly broadened photo-response and efficient photon-to-electron conversion. More encouragingly, narrowband photomultiplication (PM)-type PPDs based on poly(3-hexylthiophene-2,5-diyl) (P3HT):PY3Se-1V were developed, delivering an exceptionally high external quantum efficiency of 3680% and a responsivity of 28 A W–1at an NIR peak of 960 nm under −50 V bias, which is reported for the first time in PM-type PPDs with a response approaching 1000 nm.

Developing novel third component is critical for the ternary organic solar cells (TOSCs). Herein, we design and synthesize two novel third components, MAZ-1 and MAZ-2, with 1,3-diethyl-2-thiobarbituric acid and 1,3-dimethylbarbituric acid as the weak electron withdrawing end groups, respectively. Both MAZ-1 and MAZ-2 could improve the photovoltaic performance of the binary OSCs based on D18:Y6 which exhibit the power conversion efficiency (PCE) of 17%, because the third components can optimize the phase separation, suppress the bimolecular recombination, and decrease the nonradiative energy loss in ternary blends. The PCE of the optimized TOSCs approaches 18% along with the simultaneous increase in open circuit voltage, short circuit current density, and fill factor by incorporating 10 wt % MAZ-1 and MAZ-2 in acceptors. This work enriches the building blocks for novel third components for achieving highly efficient TOSCs.

Owing to the extreme difficulty in their prevention, transverse corner cracks have been frequently observed in fine blanking steel produced on straight arc caster. In this study, the transient thermal module of Ansys was used to calculate the corner temperature distribution of a continuous casting slab. According to the actual cooling rate, a Gleeble 3500 thermal simulator was used to simulate the bending process of continuous casting, and the thermoplastic curves of test steel grades were drawn. Through the observation of fracture morphology and metallographic examination, typical precipitation detection and phase transformation temperature detection, the mechanism of corner cracks in experimental steel grades was determined and the corresponding control measures were formulated. The results showed that under the original process conditions, the corner temperature of the continuous casting slab was in the brittle temperature range of the steel grade when it entered the bending section. During the cooling process of the continuous casting slab, all Ti elements dissolved into the matrix, and the main precipitates were (Cr, Fe)XCY, while the grain boundary pinning was weak. In the high temperature brittle region, deformation-induced ferrite was produced at grain boundaries, which formed a stress concentration during the bending process which led to plastic reduction. The mixed control mode of strong cooling in the cooling stage and weak cooling in the reheating stage could not only ensure the strength of the slab shell in the vertical section, but also promoted the growth of the ferrite film induced by intergranular deformation in the strong cooling stage. It increased the maximum allowable stress of ferrite at the grain boundary. By controlling the temperature and cooling rate in the reheating stage, the growth of ferrite at the grain boundaries and the nucleation of ferrite in grains were accelerated, the stress distribution at grain boundaries and grains was uniform, and the corner cracks were eliminated.

Triplet photovoltaic materials are increasingly recognized for their potential to enhance the efficiency of organic solar cells due to the strong emission and extended exciton lifetime compared to singlet materials. The layer-by-layer (LbL) structure provides a good opportunity to produce the highly efficient triplet photovoltaic cells, which partly overcome the challenge of material miscibility between donor and acceptor or the third component through two-step deposition. This work developed two new tetradentate platinum(II) bis-carbene complexes, Pt-CF3and Pt-AD, as triplet additive for the LbL all-PSCs fabrication. Pt-AD, featuring a bulky adamantyl group, proves to be a more effective additive than Pt-CF3, as the latter largely damages the molecular packing of the host materials due to its strong aggregation behavior. Incorporating 0.2 wt% of Pt-ADinto the PBQx-TCl/PY-DT blend elevates the fill factor (FF) to 75.8 % and the PCE to 18.45 %, outperforming the control device with PCE of 17.46 %. The effective energy transfers from Pt-ADto both the donor and acceptor can be demonstrated, leading to an increased exciton yield and lifetime in the active layers. This study indicates that steric modulation of platinum(II) complex is an effective strategy of molecular design for their application in highly efficient LbL all-PSCs.

Recombining the advantages on photovoltaic parameters of two binary‐organic photovoltaics (OPVs) into one ternary cell is an efficient strategy for selecting materials, in addition to the absorption spectra complementary among the used materials. The binary‐OPVs with J71:BTP‐4F‐12 exhibit a power conversion efficiency (PCE) of 11.70%, along with a short‐circuit‐current‐density (JSC) of 23.61 mA cm−2, an open‐circuit‐voltage (VOC) of 0.841 V and a fill factor (FF) of 58.99%. Although the relatively low PCE of 10.92% and JSCof 16.59 mA cm−2are achieved in J71:ITIC‐based binary‐OPVs, the VOCof 0.935 V and FF of 70.40% are impressive compared with J71:BTP‐4F‐12‐based OPVs. Optimal ternary‐OPVs are achieved with J71:BTP‐4F‐12:ITIC as active layers by weight ratio of 1:0.48:0.72, delivering a markedly increased PCE of 13.05% with a VOCof 0.903 V, a JSCof 21.27 mA cm−2and a FF of 68.20%. An over 11.5% PCE improvement is obtained by recombining the advantages of binary‐OPVs into ternary‐OPVs with ITIC as photon harvesting reinforcing agent and morphology regulator. The good compatibility between BTP‐4F‐12 and ITIC provides large room to well optimize their relative content for achieving the well balanced three key photovoltaic parameters of ternary‐OPVs.

Ternary organic photovoltaics (OPVs) were constructed with one wide-band-gap donor PM6 and two A–D–A-type acceptors (M-series M36 and MQ5) with similar chemical structures. Power conversion efficiency (PCE) of the optimal ternary OPVs reaches 17.24% with 20 wt % MQ5 content, arising from a simultaneously increased short circuit current density (JSC) of 25.36 mA cm–2and a fill factor (FF) of 76.02% as compared to those of two binary OPVs. The photon harvesting of ternary active layers can be maximized by adjusting the MQ5 content by reason of the complementary absorption spectra of M36 and MQ5. The molecular arrangement of PM6 and M36 can be collectively optimized by introducing an appropriate amount of MQ5 as a morphology regulator for facilitating effective charge transportation in ternary active layers. The improved photon harvesting and charge transport in active layers should be two important factors responsible for JSCand FF improvement of optimal ternary OPVs, respectively. More than an 8.8% improvement of PCE is achieved in ternary OPVs with an appropriate amount of MQ5 as the photon-harvesting enhancer and morphology regulator. The huge potential of A–D–A-type materials in constructing highly efficient OPVs can be further exploited based on a ternary strategy.

Recently, multiscale three-dimensional (3D) structures consisting of micrometer-scale structure and nanometer-scale structure have received some attention from scientists in the field of surface-enhanced Raman scattering (SERS). In this work, micrometer-scale grating structure and nanometer-scale zinc oxide nano spikes (ZnO NSs) structure are successfully introduced into the SERS substrate with silver nanoparticles (Ag NPs) as the surface plasmon. The optimized particle-in-multiscale 3D substrate (PDMS/grating/ZnO NSs/Ag NPs) presents high sensitivity with an ultralow limit of detection of 1 × 10−11M and a high enhancement factor of 7.0 × 108for Rhodamine 6G (R6G) as the probe molecule. It benefits from the electromagnetic field enhancement from the excellent optical capture capability of grating/ZnO NSs structure and abundant electromagnetic hot spots. The quantitative analysis ability of the SERS substrate can be indicated from the good linear correlation between the logarithmic Raman intensity and the molecular concentration. At the same time, this SERS substrate exhibits excellent homogeneity and reproducibility, which have low relative standard deviations (4.43%) of the Raman intensities at 613 cm−1peaks for R6G as the probe molecule. In addition, this SERS substrate can realize in-situdetection of Raman signal due to its excellent light transmission and flexibility. The particle-in-multiscale 3D structure as SERS substrate exhibits the vast potential in practical applicability for qualitatively and quantitatively chemical and biomedical analysis.

Charge injection is a basic transport process that strongly affects performance of optoelectronic devices such as light-emitting diodes and photodetectors. In these devices, the charge injection barrier is related to the band bending at the active layer/electrode interface and exhibits sophisticated dependence on interface structure and device operating conditions, making it difficult to determine via either theoretical prediction or experimental measurements. Here, in operandocross-sectional scanning Kelvin probe microscopy (SKPM) has been applied in organic photodetectors to visualize the interfacial band bending. The photoinduced interfacial band bending becomes more significant with increasing reverse bias voltage, resulting in reduced charge injection barrier and facilitated charge injection. The photoinduced injection current is orders of magnitude higher than the photocurrent directly generated from light absorption and thus leads to significant photomultiplication. Furthermore, the interfacial structure is tuned to further enhance photoinduced interfacial band bending and the photomultiplication factor.

Bottom surface of active layers and interface of indium tin oxide (ITO) electrodes and active layers play a crucial role in determining the performance of polymer photodetectors with photomultiplication (PM-PPDs). The interfacial trapped electron distribution closing to ITO electrodes will determine spectral response range and external quantum efficiency (EQE) of PMPPDs. The bottom interface is more sensitive than top interface when light is coming from the ITO side, and the larger density of generated charge on the bottom interfaces will induce interfacial band more bending for efficient charge tunneling injection. Highly sensitive and sub-microsecond PM-PPDs are achieved with PMBBDT:Y6 (100:7, w/w) as active layers under forward bias, yielding EQE of 18,700% at 320 nm, 21,700% at 600 nm and 16,400% at 810 nm under a bias of 7 V, respectively, as well as fast response time of 79 μs. The high EQE of the PM-PPDs is attributed to efficient hole tunneling injection from ITO electrode under forward bias. The electron traps closing to ITO electrode will be quickly filled up when light is coming from ITO side, leading to interfacial band more bending for hole tunneling injection. Importantly, the PM-PPDs is performed to measure heart rate (HR) and blood oxygen saturation (SpO2), and the measured data by the PM-PPDs are very similar with those obtained by commercial photodetectors.

A power conversion efficiency (PCE) of 14.46% is achieved due to the well trade-off between phase separation and photon harvesting. The 14.46% PCE should be among the highest values for SMPVs.

Photomultiplication-type polymer photodetectors (PM-PPDs) were fabricated with hole-only transport active layers containing polymer(s): [6,6]-phenylC61-butyric acid methyl ester (PC61BM) with a weight ratio of 100:2. The rather less PC61BM content in active layers prefers to generate a large amount of isolated electron traps surrounded by polymers. Photogenerated electrons prefer to be trapped by the isolated PC61BM due to the lack of continuous electron-transport channels. The trapped electrons by the isolated PC61BM close to the Al electrode would like to seduce hole tunneling injection. The transparent polymer poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine] (poly-TPD) was incorporated as a regulator to improve hole mobility (μh) and adjust the trapped-electron distribution in active layers, leading to the enhanced performance of PM-PPDs. The optimal PM-PPDs were achieved using poly(3-hexylthiophene) (P3HT):poly-TPD:PC61BM (80:20:2, wt/wt/wt) as active layers. External quantum efficiency (EQE) values at 620 nm are 3900 and 1250% for PM-PPDs based on P3HT:poly-TPD:PC61BM (80:20:2, wt/wt/wt) and P3HT:PC61BM (100:2, wt/wt) under −10 V applied voltage, respectively. The EQE at 620 nm of optimal PM-PPDs is improved from 650 to 63,000% along with the applied voltage increase from −5 to −20 V. This work provides a new strategy of using transparent polymer with large μhas a regulator for EQE and response speed improvement, as well as the flattened EQE spectral shape of PM-PPDs.

The purpose of this research is to illustrate the working principle of the voice coil motor (VCM) injector and to conduct a simulation study on the static electromagnetic characteristics of its internal voice coil motor based on Ansoft Maxwell. The selected parameters include current density parameters (ampere-turns) and related structural parameters of the VCM, including the thickness of yoke, the height of magnetizer, and the position of the coil within yoke chamber. The influence of different parameters on electromagnetic force is obtained and the reasons are explained in detail. This research is helpful to the multi-parameter optimization of the VCM injector, which will improve the electromagnetic conversion efficiency and enhance the electromagnetic force and response capability of the VCM injector.

Objective Both selenium (Se) deficiency and mycotoxin T2 lead to epiphyseal plate lesions, similar to Kashin-Beck disease (KBD). However, regulation of selenoproteins synthesis mediated by SECISBP2, in response to these 2 environmental factors, remained unclear. The present study proposed to explore the mechanism behind the cartilage degradation resulting from Se deficiency and mycotoxin T2 exposure.Design Deep chondrocyte necrosis and epiphyseal plate lesions were replicated in Dark Agouti (DA) rats by feeding them T2 toxin/Se deficiency artificial synthetic diet for 2 months.Results Se deficiency led to decreased expression of COL2α1, while T2 treatment reduced the heparan sulfate 6-O-sulfotransferase 2 (HS6ST2) expression, both of which affected the cartilage extracellular matrix metabolism in the rat models. The expression of Col2α1, Acan, Hs6st2, Secisbp2, Gpx1, and Gpx4 were all significantly decreased in cartilage tissues from DA rats, fed a Se-deficient diet or exposed to T2 toxin, contrary to Adamts4, whose expression was increased in both conditions. In addition, T2 treatment led to the decreased expression of SBP2, GPX1, GPX4, and total GPXs activity in C28/I2 cells.Conclusion DA rats exposed to T2 toxin and/or Se-deficient conditions serve as the perfect model of KBD. The 2 environmental risk factors of KBD, which serve as a “double whammy,” can intensify the extracellular matrix metabolic imbalance and the antioxidant activity of chondrocytes, leading to articular cartilage degradation and epiphyseal plate abnormalities similar to those observed in KBD.

Novel cores for high performance nonfullerene acceptors (NFAs) remain to be developed. In this work, two new n-type nitrogen-containing organic heterocyclic NFAs, namely, BDTN-BF and BDTN-Th, were designed and synthesized based on a new seven fused-ring core (BDTN) with two different end-capping groups. As a result, BDTN-BF possessed similar absorption spectra in solution and solid state to BDTN-Th, but a slightly higher maximum molar extinction coefficient. Manufacturing the polymer solar cells with PM6 as the donor, the photovoltaic performance of BDTN-BF and BDTN-Th was investigated. The PM6:BDTN-BF-based device achieved the highest power conversion efficiency (PCE) of 11.54% with a high Jscof 20.20 mA cm–2, a fill factor (FF) of 61.46%, and a large Vocof 0.93 V, and the energy loss (Eloss) was calculated to be 0.48 eV. Comparatively, the PM6:BDTN-Th-based device achieved the maximum PCE value of only 3.53% because of inadequate Jscand FF. The higher Jscand FF for the PM6:BDTN-BF-based device was mainly due to the effective electron transfer from PM6 to BDTN-BF, more balanced μh/μe, higher electron mobility of the neat film, better charge collection and dissociation efficiency, and more favorable morphology. These results demonstrate that the acceptors with nearly identical absorption spectra could result in a significant difference in photovoltaic performance, which stress the importance of end-capping units. Furthermore, few NFA-based devices achieve large Vocand high Jscsimultaneously as one based on PM6:BDTN-BF, indicating that nitrogen hybridization of NFAs may be an efficient strategy to realize high and balanced Vocand Jsc.

Ternary organic photovoltaics (OPVs) are fabricated with PBDB-T-2Cl:Y6 (1:1.2, wt/wt) as the host system and extra PC71BM as the third component. The PBDB-T-2Cl:Y6 based binary OPVs exhibit a power conversion efficiency (PCE) of 15.49% with a short circuit current (JSC) of 24.98 mA cm−2, an open circuit voltage (VOC) of 0.868 V and a fill factor (FF) of 71.42%. A 16.71% PCE is obtained in the optimized ternary OPVs with PBDB-T-2Cl:Y6:PC71BM (1:1.2:0.2, wt/wt) active layer, resulting from the synchronously improved JSCof 25.44 mA cm−2, FF of 75.66% and the constant VOCof 0.868 V. The incorporated PC71BM may prefer to mix with Y6 to finely adjust phase separation, domain size and molecular arrangement in ternary active layers, which can be confirmed from the characterization on morphology, 2D grazing incidence small and wide-angle X-ray scattering, as well as Raman mapping. In addition, PC71BM may prefer to mix with Y6 to form efficient electron transport channels, which should be conducive to charge transport and collection in the optimized ternary OPVs. This work provides more insight into the underlying reasons of the third component on performance improvement of ternary OPVs, indicating ternary strategy should be an efficient method to optimize active layers for synchronously improving photon harvesting, exciton dissociation and charge transport, while keeping the simple cell fabrication technology.

Photomultiplication (PM) type all-polymer photodetectors (all-PPDs) are first demonstrated with the sandwich structure of ITO/PEDOT:PSS/PBDB-T:PZ1 (100:x, wt/wt)/Al. The optimal PM type all-PPDs with PBDB-T:PZ1 (100:3, wt/wt) as active layers exhibit external quantum efficiency (EQE) of >100% in the spectral range from 310 to 790 nm. Under 675 nm light illumination, the champion EQE value arrives to 1,470% at −20 V bias and the specific detectivity approaches 1×1012Jones at −10 V bias. The PM phenomenon in all-PPDs results from hole tunneling injection assisted by interfacial band bending induced by trapped electrons in PZ1 near Al electrode. The EQE values of optimal PM type all-PPDs still remained over 90% of the original value after 60 d of the storage in a high-purity nitrogen-filled glove box.