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Aiming at the problem of the application of the integrated photonic filter in the 3～5 μm atmospheric window banda mid-infrared add-drop filter based on the apodized grating-assisted contra-directional coupler (contra-DC) is studied and designed. The complementary lateral-misalignment method is used for phase modulation to achieve spectral sidelobe suppression and eliminate spectral distortion and broadening caused by the conventional lateral-misalignment modulation method. Simulation results show that the device can achieve a high Sidelobe Suppression Ratio (SLSR) of 22 dB, bandpass filter spectrum is flat at the top and the filtering spectrum is close to the box shape. The device has low insertion loss of about 0.4 dB through port and 0.45 dB drop port.

For the problem of inhomogeneity of the output optical power of multiple output ports, the paper designs a 1×4 Multimode Interference (MMI) coupler based on Silicon-On-Insulator (SOI) and proposes a new method to optimize its homogeneity. A tapered waveguide is used at the input/output of the coupler. To improve the uniformity of the MMI coupler, an unequal-width design is used for the tapered waveguide at the output. After optimization, the uniformity of the four output ports is as high as 0.007 4 dB, while the total insertion loss is only 0.058 dB. According to this method, the transmission constant of the output, avoid crosstalk between waveguides, and achieve an improvement in the uniformity of the output port of the MMI coupler.

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The application of metal-free photosensitizers in dye-sensitized photoelectrochemical cells (DSPECs) has attracted great interest due to their low cost in recent years. However, there is an urgent need to develop novel metal-free water oxidation catalysts (WOCs) for DSPECs. In this work, for the first time, three linear conjugated oxygen-producing polymers (OPPs) are introduced into the DSPEC system with calixarene photosensitizers to achieve visible light-driven total water splitting. The best performance is demonstrated by the FTO‖TiO2‖C4EOP + Oxamide-PDI photoanode, giving a photocurrent density of 208 μA cm−2 after 200 s of chopping irradiation at 0.2 V vs. the reversible hydrogen electrode (RHE). Further, Faraday efficiencies of 86.1% at 0.2 V vs. RHE and 66.3% without a bias voltage for oxygen production are obtained. C4EOP-sensitized electrodes exhibit higher photocurrent densities due to their superior light absorption performance, greater electron–hole recombination impedance, and stronger affinity to hydrophilic polymers. Oxamide-PDI loaded electrodes show better performance due to their higher crystallinity and larger π-conjugation width. This is a pioneering study to incorporate OPPs as WOCs into the calixarene-sensitized DSPEC system, which has significant potential as a low-cost and high-efficiency device for photoelectrochemical water splitting. [ABSTRACT FROM AUTHOR]

Phytochemical study on 90% ethanol extract from the green walnut husks of Juglans mandshurica Maxim. resulted into the isolation of three undescribed triterpenoids, juglansmanoids A–C (1–3). Structural elucidation of all the compounds were performed by spectral methods such as 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated components were evaluated in vitro for anti-hyaluronidase activities. As a result, triterpenoid 1 exhibited potent anti-hyaluronidase activity (IC50 = 9.78 μg/ml) three times more than the positive control drug oleanolic acid (IC50 = 40.12 μg/ml). [ABSTRACT FROM AUTHOR]

This study investigated the mechanical properties and antibacterial properties of hexagonal boron nitride and titanium dioxide (h-BN-TiO2) nanocomposite modified traditional glass ionomer cement. The mechanism of formation of the h-BN-TiO2 nanocomposite was elucidated by conducting molecular dynamics (MD) simulations using the Material Studio (MS) software. Furthermore, synthesis of h-BN-TiO2 nanocomposite by the original growth method using hexagonal boron nitride nanosheets (h-BNNs) and titanium dioxide nanoparticles (TiO2 Nps) and characterization using TEM and AFM to determine their particle sizes, morphologies, and structures. The mechanical properties and antibacterial efficacies of the glass ionomer cement composites were analyzed based on the different mass fractions (0, 0.3, 0.7, 1.1, and 1.5 wt%) of the h-BN-TiO2 nanocomposite. The results showed when the concentration of the h-BN-TiO2 nanocomposite was 1.1 wt%, the Compressive strength (CS) and Vicker hardness (VHN) were 80.2% and 149.65% higher, respectively, compared to the glass ionomer cement without any h-BN-TiO2 nanocomposite. Also, the increase in the concentration of the h-BN-TiO2 nanocomposite led to a decrease in both the coefficient of friction (COF) and solubility, but a 93.4% increase in the antibacterial properties of the glass ionomer cement composites. The cell survival rate of each group was more than 70% after 48 h, but the difference was not statistically significant (p > 0.05). Therefore, the h-BN-TiO2 nanocomposite served as a reinforcing material for glass ionomer cement, which can be useful in clinical dentistry and provide a new strategy for improving the clinical utility of glass ionomer cement.

Nano-SiO2 surface grafted APTES (T-SiO2) was realized by covalent functionalization technology, and functionalized nano-SiO2 modified epoxy resin composite (T-SiO2/EP) was prepared. The surface functional groups and chemical elements of the functionalized nano-SiO2were analyzed and the mechanical and tribological properties of the T-SiO2/EP were tested. The results show that the mechanical and tribological properties of the epoxy resin are effectively improved due to the introduction of functionalized nano-SiO2. When the content of functionalized nano-SiO2 is 2%(mass fraction, same as below), the microhardness and fracture toughness of the composites (2%T-SiO2/EP) can reach the maximum, which are 70.2HD and 1.02MPa·m1/2 respectively, moreover, in dry friction condition, the friction coefficient and the wear loss reach the minimum, which are 0.49mg and 1.7mg respectively. Compared with pure epoxy resin, they are reduced by 31.9% and 34.6%, and compared with 2% unmodified nano-SiO2 reinforced epoxy resin composite, they are reduced by 14% and 10.5%,and the corresponding wear mechanism is analyzed.

Abstract As an important online information retaining and processing function, working memory plays critical roles in many other cognitive functions. Several long-term factors, such as age, addiction and diseases, have been affirmed to impair working memory, but whether or how the short-term factors, like painful stimuli or emotions, regulate the human working memory ability is not well explored. Here we investigated the influences of empathic pain on upcoming working memory and existing working memory, by presenting human subjects with the pictures depicting painful or neutral scene. After separating the subjects into two groups, the more empathic group and relatively indifferent group, according to a well-accepted questionnaire (the Interpersonal Reactivity Index (IRI)), the modulatory effect emerged. Empathic pain might exerted either a facilitating effect or an impairing effect, which was closely correlated with the personal empathy skills. Meanwhile, different aspects of subjects’ empathy traits exerted distinct effects, and female subjects were more vulnerable than male subjects. Present study reveals a new modulatory manner of the working memory, via empathy skill-dependent painful experience.

The electricity transmission and distribution tariff policy of the second supervision cycle in China has formulated a much better electricity transmission and distribution tariff supervision system. In this context, the research on the risk related to electricity transmission and distribution tariff regulation faced by power grid enterprises is helpful for power regulatory agencies and business operators to identify and avoid risks in time and promote the sustainable development of electric power industry. Firstly, the risk evaluation criteria system is established. Secondly, a risk evaluation model based on the best and worst method (BWM) and cloud model for electricity transmission and distribution tariff regulation is proposed. Finally, the risk level of power transmission and distribution tariff regulation faced by four provincial power grid enterprises is evaluated. The validity and practicability of the proposed model in this paper are proved by the empirical analysis.