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In order to solve the problems of low transmission rate and large device size of electro-optical modulator, an electro-optic half subtractor based on silicon-based hybrid surface plasmon polariton waveguide is proposed in this study. The proposed device utilizes three units metal-oxide-semiconductor capacitor structure to achieve the half subtractor logic function of electro-optic control, improving the transmission rate of the electro-optic half subtractor while also reducing the device size using surface plasmon polariton technology, with a size of only 32 μm × 4.3 μm. At the same time, the use of hybrid silicon waveguides reduces the sharp Ohmic attenuation caused by surface plasmon polaritons and reduces optical insertion losses (ILs). The simulation results show that when the electro-optic half subtractor operates at the wavelength of 1,550 nm, the IL difference is 1.0 dB in each state, the transmission rate of the device is 0.75 Tbit/s, and the energy consumption is 12.69 fj/bit.

This article proposes an on-chip optical temperature sensor based on a cascaded microring resonator, which is composed of a reference ring and a sensing ring cascaded with different temperature sensitivities and free spectral ranges. By changing the temperature of the sensing window environment, the thermal optical effect of the waveguide causes a change in the refractive index of the waveguide, which affects the temperature sensitivity and free spectrum changes of the sensor. The output spectral response of the sensor shifts, achieving temperature sensing detection. The experimental results show that the temperature sensitivity of this microring cascaded temperature sensor is 303.6 pm/°C, which is 3.65 times the limit of a single microring temperature sensitivity of 83 pm/°C. The temperature-sensing range of the sensor is 100°C, which can well meet the temperature-monitoring requirements of ultra-large-scale integrated circuits.

Digital multipliers are the core components of digital computers, and improving the speed of transistor electronic computers during computation has almost reached its limit, with high power consumption. In this paper, we proposed an electro-optic hybrid multidigit digital multiplier based on SPP technology, which has the advantages of high speed and low power consumption in optical logic, as well as flexible electrical operation and easy storage. The electro-optic hybrid digital multiplier mainly consists of an electrical AND logic gate, an electro-optic hybrid half adder, and an electro-optic hybrid full adder. The optical logic unit is controlled by activated ITO materials to achieve optical-domain operations, and then the multiplication calculation results are converted into electrical signals through photoelectric conversion. The experimental results show that when the scale is 64 × 64 bits, compared with transistor digital multiplication, the energy consumption is reduced by 48.8%; the speed is increased by a factor of 28; and the volume of the electro-optic hybrid digital multiplier device is larger than that of the transistor multiplier, saving 59.9% of the area. For optical transmission loss, a single adder outputs 0.31 dB at different device scales, while the carry output continuously increases with device scale. At scales of 8 × 8 bits, 16 × 16 bits, and 64 × 64 bits, the insertion losses at the sum output ports are 1.03 dB/μm and 1.87 dB/μm, respectively. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction catalysts capable of working efficiently in acidic media are highly demanded for the commercialization of proton exchange membrane water electrolysis. Herein, we report a Zn-doped RuO2 nanowire array electrocatalyst with outstanding catalytic performance for the oxygen evolution reaction under acidic conditions. Overpotentials as low as 173, 304, and 373 mV are achieved at 10, 500, and 1000 mA cm−2, respectively, with robust stability reaching to 1000 h at 10 mA cm−2. Experimental and theoretical investigations establish a clear synergistic effect of Zn dopants and oxygen vacancies on regulating the binding configurations of oxygenated adsorbates on the active centers, which then enables an alternative Ru−Zn dual-site oxide path of the reaction. Due to the change of reaction pathways, the energy barrier of rate-determining step is reduced, and the over-oxidation of Ru active sites is alleviated. As a result, the catalytic activity and stability are significantly enhanced. Ru-based materials are promising catalysts for oxygen evolution reaction in acidic condition, but their catalytic performance needs to be further improved. Here, the authors report Zn-RuO2 nanowires with a Ru−Zn dual-site oxide reaction pathway with enhanced activity and stability for acidic oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Background: Laccase, a multicopper oxidase that catalyzes the oxidation of phenols, aromatic amines, and benzenethiols, has attracted much attention in applications of organic synthesis, bioremediation, and pulp/textile bleaching. However, free laccases cannot be recycled and are easily inactivated in diverse environmental conditions. Enzyme immobilization is a promising strategy to improve stability, resistance to extreme conditions, and reusability of laccase.Results: In this study, amino-functionalized magnetic Fe3O4 nanoparticles were synthesized for co-immobilization of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and laccase by glutaraldehyde cross-linking method. The magnetic nanoparticles were characterized with FTIR, XRD and VSM. Cyclic voltammetry was carried out to verify electrochemical behaviors of the co-immobilized laccase and TEMPO nanoparticles. When the co-immobilized laccase and TEMPO nanoparticles were used to decolorize acid fuchsin, the maximum decolorization rate of 77.41% was obtained with the ratio of TEMPO to laccase being 0.3 mM/g:120 U/g.Conclusion: The co-immobilized nanoparticles retained above 50% residual activity after eight cycles of operation, which presented an approach to develop a co-immobilized laccase and mediator system for potential industrial application. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S) is the most recently discovered gasotransmitter molecule that activates multiple intracellular signaling pathways and exerts concentration-dependent antitumor effect by interfering with mitochondrial respiration and inhibiting cellular ATP generation. Inspired by the fact that H 2 S can also serve as a promoter for intracellular Ca 2+ influx, tumor-specific nanomodulators (I-CaS@PP) have been constructed by encapsulating calcium sulfide (CaS) and indocyanine green (ICG) into methoxy poly (ethylene glycol) -b- poly (lactide -co- glycolide) (PLGA-PEG). I-CaS@PP can achieve tumor-specific biodegradability with high biocompatibility and pH-responsive H 2 S release. The released H 2 S can effectively suppress the catalase (CAT) activity and synergize with released Ca 2+ to facilitate abnormal Ca 2+ retention in cells, thus leading to mitochondria destruction and amplification of oxidative stress. Mitochondrial dysfunction further contributes to blocking ATP synthesis and downregulating heat shock proteins (HSPs) expression, which is beneficial to overcome the heat endurance of tumor cells and strengthen ICG-induced photothermal performance. Such a H 2 S-boosted Ca 2+ -involved tumor-specific therapy exhibits highly effective tumor inhibition effect with almost complete elimination within 14-day treatment, indicating the great prospect of CaS-based nanomodulators as antitumor therapeutics., Competing Interests: The authors declare no conflict of interest., (© 2022 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)