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Acid value, as an important indicator of its oxidation and quality, is used to measure the content of free fatty acid (FFA) in edible vegetable oil. At present, titration is the most widely used method to examine the acid value of edible oil, which is simple and easy to operate. Titration is effective for the detection of acid in most edible oils, but the detection error rate is higher for edible oil with lower acid value, darker color or certain interference components except FFA. Instrumental analysis methods, such as spectroscopy,electrochemistry, colorimetry and chromatography, can be used as alternatives to titration. Besides, the instrumental analysis methods have better sensitivity and accuracy. In order to further expand and innovate the technology of acid value detection in edible vegetable oil, the production pathway of edible vegetable oil FFA, the features and current situation of acid value detection methods are analyzed and compared, to provide reference for the improvements of acid value detection method and the establishment of new methods.

Deep‐red and near‐infrared emitters with twisted donor–acceptor (D–A) structures often exhibit suboptimal performance in organic light‐emitting diodes (OLEDs) due to constraints imposed by the energy gap law. In this work, a pure hydrogen carbon (PHC) host material named SBF‐DTP is purposefully tailored for deep‐red OLEDs. The excellent capacity of SBF‐DTP to support D–A type DR emitters effectively arises from its distinctive attributes: localized excitation states, 3D configuration, and low polarity. When employing SBF‐DTP as the host for the fluorescence emitter DCPA‐TPA and the thermally activated delayed fluorescence emitter APDC‐DTPA, doped films exhibit substantially enhanced photoluminescence quantum yields. This improvement leads to high‐efficiency OLEDs with external quantum efficiencies of 5.47% for DCPA‐TPA and 20.03% for APDC‐DTPA, respectively, which is about twice as high as the initial reports. This findings underscore the paramount significance of developing efficient host materials in the pursuit of high‐performance deep red and even near‐infrared OLEDs. [ABSTRACT FROM AUTHOR]

Existing model synchronization mechanisms of federated learning (FL) are mostly based on single-layer parameter server architecture,which are difficult to adapt to current heterogeneous wireless network scenarios.There are some problems such as excessive communication load on single-point and poor scalability of FL.In response to these problems,this paper proposes an efficient model synchronization scheme for FL in hybrid wireless edge networks.In a hybrid edge wireless network,edge devices transmit local models to nearby small base stations.After receiving local models from edge devices,small base stations exe-cute the aggregation algorithm and send the aggregated models to the macro base station to update the global model.Considering the heterogeneity of channel performance and the competitive relationship of data transmission on the wireless channel,this paper proposes a new type of grouping asynchronous model synchronization scheme and designs a transmission rate aware channel allocation algorithm.Experiments are carried out on real data sets.Experimental results show that the proposed transmission rate aware channel allocation algorithm in grouping asynchronous model synchronization scheme can reduce communication time by 25%～60% and greatly improve the training efficiency of FL.

Red to near-infrared organic light-emitting diodes (OLEDs) utilizing thermally activated delayed fluorescence (TADF) emitters continue to exhibit significant external quantum efficiency (EQE) roll-off at high luminance levels exceeding 1000 cd m−2, attributed to the relatively modest reverse intersystem crossing rate constant (kRISC) of approximately 103–104 s−1. This study presents a novel TADF molecule, TCPP-DTPA, featuring a structurally rigid π-stacked multiple donor/acceptor design. The enhanced donor/acceptor interactions minimize the energy gap between the singlet and triplet states of the TCPP-DTPA, allowing for an efficient RISC process with a high rate constant of 4.67 × 106 s−1. The OLED utilizing TCPP-DTPA demonstrates a peak EQE of 23.5% at a wavelength of 618 nm. Additionally, notable EQE values of 7.8% and 14.9% are observed at a luminance of 1000 cd m−2 for OLEDs without and with an energy-transfer assistant dopant in the emissive layer, respectively. This research contributes to enhancing the efficiency of high-brightness red TADF OLEDs, while also offering valuable insights for the optimization of molecular design and device engineering to mitigate the electroluminescence efficiency roll-off. [ABSTRACT FROM AUTHOR]

Bulk gallium nitride (GaN) has shown great success in light‐emitting diodes (LEDs), but the use of its counterpart GaN quantum dots (QDs) to obtain electroluminescence has not yet been reported. In this work, the first GaN‐based QLED is demonstrated using Zn‐doped GaN (GaN: Zn) QDs, which is achieved through the combination of trap passivation, energy level adjustment, and morphology engineering. Pure GaN QDs and GaN: Zn QDs are synthesized, and it is found that Zn doping shifts the GaN QD emission from 321 to 377 nm and tunes the highest occupied molecular orbital energy level from 8.6 eV (of original GaN QDs) to 6.9 eV. Multiple washing posttreatment is further developed to improve QD film morphology and size distribution. The optimized GaN: Zn QDs are employed to fabricate solution‐processed LEDs, and the first GaN‐based QLEDs are reported with a maximum quantum efficiency of 0.004%. [ABSTRACT FROM AUTHOR]