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Preventing the accretion of droplets on surfaces is vital and slippery liquid‐infused porous surfaces (SLIPS) have promising application prospects, such as surface self‐cleaning and droplet transportation. In this work, controllable self‐transport of bouncing droplets on ultraslippery surfaces with wedge‐shaped grooves is reported. The impact behaviors of droplets on SLIPS under various impact velocities and diameters are explored, which can be classified as hover, total bounce, partial bounce, Worthington jet, and crush. SLIPS with wedge‐shaped grooves were designed to transport accreted droplets. An energy and transport model is established to explain the impact and self‐transport mechanism, where the Laplace pressure and moving resistance between droplets play a key role. Finally, SLIPS with branched wedge‐shaped grooves were designed for droplet self‐transport and demonstrated advantages. This work provides a general reference for spontaneous motion control of sessile droplets, droplets with initial impacting velocity, or even liquid films. [ABSTRACT FROM AUTHOR]

This article presents a dual‐band filtering power amplifier (DB‐FPA) with extended passband bandwidths and wide stopband rejection, which is helpful in reducing the number of microwave components in the dual‐band radio frequency front end, resulting in compact circuit size and low loss. In the designed DB‐FPA, a wideband low‐pass filter is applied as the input matching network (IMN) to provide wideband impedance matching and good stopband rejection, while a dual‐band filtering impedance transformation is adopted as the output matching network (OMN) to provide dual‐band impedance matchings and filtering responses simultaneously. Specifically, the IMN is constructed by high‐impedance transmission‐line sections and low‐impedance open‐circuit stubs. The OMN is designed based on the specific external quality factors and coupling coefficients during two bands, resulting in dual‐band impedance transformations and dual‐band filtering responses. Then, based on the above IMN and OMN, the design procedure of the presented DB‐FPA is summarised. To verify the proposed idea, a novel DB‐FPA has been fabricated and measured. During the two frequency bands, the measured maximum power added efficiencies are 55.11% and 47.78% within 33.0 dBm input power, while the measured peak gains are 15.4 and 14.0 dB within 15.0 dBm input power. [ABSTRACT FROM AUTHOR]

The integration of the Mobile Crowdsensing (MCS) and Industrial Internet of Things (IIoT) brings enormous volumes of data that generate significant commercial value. However, the data contain a wealth of sensitive information about devices' environmental situation and collective activities, which draws a flock of adversaries and poses an unprecedented security challenge. Furthermore, sensing gadgets deployed in the IIoT device are usually resource‐constrained and often do not have adequate 3C resources (i.e. communication, computing, caching) to run sophisticated privacy‐preserving methods, making them easier targets for attacks in data sharing. Therefore, a risk‐adaptive privacy protection scheme R‐DP for MCS‐enabled IIoT gadgets is proposed, which comprises a closed‐loop risk‐awareness process and an adaptive privacy protection method DP (a dissemination process with perturbation). The closed‐loop process dynamic awareness of risks and threats in MCS task feeds appropriate privacy protection advice to the decision‐makers for the task. In addition, DP was designed as a lightweight and risk‐adaptive privacy protection method to meet the operational needs of 3C resource‐constrained gadgets. The analysis and evaluation show that R‐DP provides satisfactory privacy protection while the availability of statistical features reaches more than 96%, and the time complexity is only O (1) for sensing gadgets. [ABSTRACT FROM AUTHOR]

With the rapid development of new energy sources and the increasing proportion of electric vehicles (EVs) connected to the power grid in China, peak load regulation of power systems will face severe challenges. Therefore, in this study, we analyzed the relationship between the electricity consumption characteristics of EVs and the peak load regulation (PLR) mechanism of power systems, and we proposed an operation mode for virtual power plants with EVs to participate in the auxiliary service market and facilitate deep peak load regulation in the thermal power units. Based on the electricity demand‐side management theory and cost‐benefit analysis method, we constructed a decision model for economic deep peak load regulated operation (DPLR) of the auxiliary thermal power units in a virtual power plant with EVs, aiming to optimize the operation efficiency. The case study showed that a virtual power plant that included EVs can effectively reduce the total PLR cost of the system and the peak valley difference of the net load as well as improve the economic benefits of the thermal power units. The results indicated that the virtual power plant had improved economic efficiency. Therefore, the results of this research can help improve the PLR capacity of the grid and significantly promote the consumption of intermittent renewable energy. [ABSTRACT FROM AUTHOR]

Irinotecan is a kind of alkaloid with antitumour activity, but its low solubility and high toxicity limit its application. Epigallocatechin‐3‐gallate (EGCG) is one of the main bioactive components in tea. The epidemiological investigation and animal and cell experiments show that EGCG has a preventive and therapeutic effect on many kinds of tumours. Here, colorectal cancer cells RKO and HCT116 were employed, and the CCK8 proliferation test was used to screen the appropriate concentration of EGCG and irinotecan, and the effects of single and/or combined drugs on migration, invasion, DNA damage, cell cycle and autophagy of tumour cells were investigated. The results showed that EGCG combined with irinotecan (0.5 μmol L−) not only had a stronger inhibitory effect on tumour cells than EGCG or irinotecan alone but also prevented tumour cell migration and invasion. EGCG alone did not cause DNA damage in colorectal cancer cells, but its combination with irinotecan could induce S or G2 phase arrest by inhibiting topoisomerase I to cause more extensive DNA damage. EGCG also induced apoptosis by promoting autophagy with irinotecan synergistically. These results indicated that EGCG in combination with irinotecan could be a promising strategy for colorectal cancer. [ABSTRACT FROM AUTHOR]

Abstract: Organic light‐emitting diodes (OLEDs) are one of the most promising technologies for future displays and lighting. Compared with the blue and green OLEDs that have achieved very high efficiencies by using phosphorescent Ir(III) complexes, the red OLEDs still show relatively low efficiencies because of the lack of high‐performance red‐emitting Ir(III) complexes. Here, three highly efficient asymmetric red‐emitting Ir(III) complexes with two different cyclometalating ligands made by incorporating only one electron‐deficient triarylboron group into the nitrogen heterocyclic ring are reported. These complexes show enhanced photoluminescence quantum yields up to 0.96 and improved electron transporting capacity. In addition, the asymmetric structure can help to improve the solubility of Ir(III) complexes, which is crucial for fabricating OLEDs using the solution method. The photoluminescent and oxidation–reduction properties of these Ir(III) complexes are investigated both experimentally and theoretically. Most importantly, a solution‐processed red OLED achieves extremely high external quantum efficiency, current efficiency, and power efficiency with values of 28.5%, 54.4 cd A−1, and 50.1 lm W−1, respectively, with very low efficiency roll‐off. Additionally, the related device has a significantly extended operating lifetime compared with the reference device. These results demonstrate that the asymmetric diarylboron‐based Ir(III) complexes have great potential for fabricating high‐performance red OLEDs. [ABSTRACT FROM AUTHOR]

Phosphorescent near‐infrared (NIR) organic light‐emitting devices (OLEDs) have drawn increasing attention for their promising applications in the fields such as photodynamic therapy and night‐vision readable displays. Here, three simple phosphorescent Pt(II) complexes are synthesized, and their intermolecular interactions are investigated in crystals and neat films by X‐ray single crystal diffraction and grazing‐incidence wide‐angle X‐ray scattering, respectively. The photophysical properties, molecular aggregation (including Pt–Pt interaction), molecular packing orientation, and electron transport ability are all influenced by the strong intermolecular hydrogen bonds. Consequently, the nondoped OLEDs based on tBu‐Pt and F‐Pt show electroluminescent emissions in NIR region with the highest external quantum efficiencies of 13.9% and 16.7%, respectively. Because of enhanced molecular aggregations induced by strong intermolecular hydrogen bonds, a simple Pt(II) complex neat film shows near‐infrared (NIR) emission with high photoluminescence quantum yield, improved electron transport ability, and preferred molecular orientation. The related nondoped organic light‐emitting device (OLED) exhibits the near‐infrared (NIR) emission with a peak external quantum efficiency of 16.7%. [ABSTRACT FROM AUTHOR]