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Flexible optoelectronics is a rapidly growing field, with a wide range of potential applications. From wearable sensors to bendable solar cells, curved displays, and curved focal plane arrays, the possibilities are endless. The criticality of flexible photodetectors for many of these applications is acknowledged, however, devices that are demonstrated thus far are limited in their spectral range. In this study, flexible photodetectors are demonstrated using a VOx nanoparticle ink, with an extremely broad operating wavelength range of 0.4 to 20 µm. This ink is synthesized using a simple and scalable wet-chemical process. These photodetectors operate at room temperature and exhibit minimal variance in performance even when bent at angles of up to 100 ° at a bend radius of 6.4 mm. In addition, rigorous strain testing of 100 bend and release cycles revealed a photoresponse with a standard deviation of only 0.55%. This combination of mechanical flexibility, wide spectral response, and ease of fabrication makes these devices highly desirable for a wide range of applications, including low-cost wearable sensors and hyperspectral imaging systems.

Bulk black phosphorous (bP) exhibits excellent infrared (IR) optoelectronic properties, but most reported bP IR photodetectors are fabricated from single exfoliated flakes with lateral sizes of < 100 µm. Here, scalable thin films of bP suitable for IR photodetector arrays are realized through a tailored solution‐deposition method. The properties of the bP film and their protective capping layers are optimized to fabricate bP IR photoconductors exhibiting specific detectivities up to 4.0 × 108 cm Hz1/2 W−1 with fast 30/60 µs rise/fall times under λ = 2.2 µm illumination. The scalability of the bP thin film fabrication is demonstrated by fabricating a linear array of 25 bP photodetectors and obtaining 25 × 25 pixel IR images at ≈203 ppi with good spatial fidelity. This research demonstrates a commercially viable method of fabricating scalable bP thin films for optoelectronic devices including room temperature‐operable IR photodetector arrays. [ABSTRACT FROM AUTHOR]

In the process of development, new media presents a completely different development mode from traditional media, namely, platform development mode. Under the effect of network effect, the new media platform can quickly gather a large number of users, and integrate the resources of all the endpoints on the platform through the platform operation, so that the information production becomes efficient and the phenomenon of collaborative production appears. The value of media platform development is mainly reflected in the construction of its bilateral economic model, and the key to the construction of the bilateral model lies in the transformation from the scale economy of the demand side to the scope economy of the supply side. This paper explores a service-oriented new media operation platform under the bilateral market economy mode, to construct a price structure for bilateral users, from the perspective of free mechanism, attention economy and supply side economies of scope. This new media operation platform can break the barriers of single information flow, build unlimited value-added services, promote the integration of information flow, capital flow and logistics platform, and thus create a service-oriented new media platform.

Chitosan has several shortcomings that limit its practical application for the adsorption of heavy metals: mechanical instability, a challenging separation and recovery process, and low equilibrium capacity. This study describes the synthesis of a magnetic xanthate-modified polyvinyl alcohol and chitosan composite (XMPC) for the efficient removal and recovery of heavy metal ions from aqueous solutions. The XMPC was synthesized from polyvinyl alcohol, chitosan, and magnetic Fe3O4@SiO2 nanoparticles. The XMPC was characterized, and its adsorption performance in removing heavy metal ions was studied under different experimental conditions. The adsorption kinetics fit a pseudo-second-order kinetic model well. This showed that the adsorption of heavy metal ions by the XMPC is a chemical adsorption and is affected by intra-particle diffusion. The equilibrium adsorption isotherm was well described by the Langmuir and Freundlich equations. The XMPC reached adsorption equilibrium at 303 K after approximately 120 min, and the removal rate of Cd(II) ions was 307 mg/g. The composite material can be reused many times and is easily magnetically separated from the solution. This makes the XMPC a promising candidate for widespread application in sewage treatment systems for the removal of heavy metals. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyze the incidence and characteristics of adverse events following immunization (AEFI) with post-licensure vaccines used in Hebei province from 2018 to 2020 and to evaluate the safety of vaccines. All information of AEFI was gained from national adverse event following immunization surveillance system (NAEFISS) in Hebei Province from 2018 to 2020. Descriptive epidemiology method was used to analyze the data about AEFI in Hebei province. Reporting rates of AEFI were calculated by sex, age, city, categories of AEFI, severity of AEFI, reaction categories, etc. A total of 35,999 AEFI were reported through NAEFISS, and the average annual rate was 47.64/100,000 doses. The reporting rates of common adverse reactions and rare adverse reactions were 46.37/100,000 doses and 1.05/100,000 doses. The male-to-female ratio was 1.26:1. Most of the AEFI were concentrated in the ≤1 year age group and were reported in the second quarter and third quarter. The majority of AEFI were reported to be recovered or improved, and about 62% of the AEFI occurred within 24 hours after vaccination. Vaccines associated with the highest reporting rate of AEFI were diphtheria, tetanus and acellular pertussis combined vaccine (DTaP, 170.45/100,000 doses). The reporting rate of allergic rash was found to be the highest in the adverse reactions (0.29/100,000 doses). The majority of AEFI cases were common adverse reactions, while serious rare adverse reactions caused by vaccines were extremely uncommon, and all vaccines used in Hebei Province were safe.