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Vibration sensors are widely applied in the detection of faults and analysis of operational states in engineering machinery and equipment. However, commercial vibration sensors with a feature of high hardness hinder their usage in some practical applications where the measured objects have irregular surfaces that are difficult to install. Moreover, as the operating environments of machinery become increasingly complex, there is a growing demand for sensors capable of working in wet and humid conditions. Here, we present a flexible, superhydrophobic vibration sensor with parallel microcracks. The sensor is fabricated using a femtosecond laser direct writing ablation strategy to create the parallel cracks on a PDMS film, followed by spray-coating with a conductive ink composed of MWCNTs, CB, and PDMS. The results demonstrate that the developed flexible sensor exhibits a high-frequency response of up to 2000 Hz, a high acceleration response of up to 100 m/s2, a water contact angle as high as 159.61°, and a linearity of 0.9812 between the voltage signal and acceleration. The results indicate that the sensor can be employed for underwater vibration, sound recognition, and vibration monitoring in fields such as shield cutters, holding significant potential for mechanical equipment vibration monitoring and speech-based human–machine interaction. [ABSTRACT FROM AUTHOR]

Vibration sensors are widely used in many fields like industry, agriculture, military, medicine, environment, etc. However, due to the speedy upgrading, most sensors composed of rigid or even toxic materials cause pollution to the environment and give rise to an increased amount of electronic waste. To meet the requirement of green electronics, biodegradable materials are advocated to be used to develop vibration sensors. Herein, a vibration sensor is reported based on a strategy of pencil-drawing graphite on paper. Specifically, a repeated pencil-drawing process is carried out on paper with a zigzag-shaped framework and parallel microgrooves, to form a graphite coating, thus serving as a functional conductive layer for electromechanical signal conversion. To enhance the sensor's sensitivity to vibration, a mass is loaded in the center of the paper, so that higher oscillation amplitude could happen under vibrational excitation. In so doing, the paper-based sensor can respond to vibrations with a wide frequency range from 5 Hz to 1 kHz, and vibrations with a maximum acceleration of 10 g. The results demonstrate that the sensor can not only be utilized for monitoring vibrations generated by the knuckle-knocking of plastic plates or objects falling down but also can be used to detect vibration in areas such as the shield cut head to assess the working conditions of machinery. The paper-based MEMS vibration sensor exhibits merits like easy fabrication, low cost, and being environmentally friendly, which indicates its great application potential in vibration monitoring fields. [ABSTRACT FROM AUTHOR]

Flexible strain sensors are of great significance in health monitoring, wearable electronic devices, intelligent robot sensing, and other fields. Most of the reported works focus on the enhancement of sensitivity or working range, while linearity is ignored and exhibits strong nonlinearity. Conflict among performances remains a serious challenge for the development of flexible strain sensors. Herein, inspired by the architecture of butterfly's wings, a strain sensor with double conductive layers and wrinkles/holes structures is proposed. The fabricated sensor shows a high linearity of >0.98 over a full working strain range of 120%, and a linearity of up to 0.999 within a strain range of 0%–30%. Apart from that, the sensor also presents a sensitivity of 8.28, high stability over 40 000 cycles when subjected to a full‐scale strain, as well as a water contact angle of >167.4°. Meanwhile, strains as low as 0.075% can be identified, while a maximum frequency of 40 Hz can be responded to for the sensor. It is demonstrated that the sensor is capable of enabling flexible grippers to sense and monitor the motions of underwater vehicles, indicating its greater potential for diverse applications, such as human–machine interaction, marine environmental protection, and biological research. [ABSTRACT FROM AUTHOR]

Coenzyme NADH regeneration is crucial for sustained photoenzymatic catalysis of CO2 reduction. However, light‐driven NADH regeneration still suffers from the low regeneration efficiency and requires the use of a homogeneous Rh complex. Herein, a Rh complex‐based electron transfer unit was chemically attached onto the linker of the MIL‐125‐NH2. The coupling between the light‐harvesting iminopyridine unit and electron‐transferring Rh‐complex facilitated the photo‐induced electron transfer for the NADH regeneration with the yield of 66.4 % in 60 mins for 5 cycles. The formate dehydrogenase was further deposited onto the hydrophobic layer of the membrane by a reverse filtering technique, which forms the gas‐liquid‐solid reaction interface around the enzyme site. It gave an enhanced formic acid yield of 9.5 mM in 24 hours coupled with the in situ regenerated NADH. The work could shed light on the construction of integrated inorganic‐enzyme hybrid systems for artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A two-step synthesis was developed to fabricate Ag/AgBr necklace-like nano-heterostructures at room temperature. Multiple crystalline Ag nanowires were used as templates following an oxidation route in situ from CuBr2 to create Ag/AgBr heterostructures. Polyvinylpyrrolidone can govern the formation of one-dimensional Ag/AgBr necklace-like nano-heterostructures. The composition of the heterostructures was adjusted by changing the amount of CuBr2. Experimental conditions were optimized. In particular, the concentration and injection rate of copper bromide solution play an important role in controlling the oxidation of the Ag nanowires for the purpose of adjusting the morphology of the Ag/AgBr heterostructures. As a result, the heterostructures with 40 mol % AgBr displayed a regular necklace-like morphology. Under visible-light irradiation, Ag/AgBr necklace-like heterostructures with AgBr molar ratios of 10 to 50 % exhibited enhanced plasmonic photocatalytic performance for the degradation of organic pollutants (methyl orange, methylene blue, and rhodamine B). [ABSTRACT FROM AUTHOR]

Abstract  Light state transition is a physiological function of oxygenic organisms to balance the excitation of photosystem II (PSII) and photosystem I (PSI), hence a prerequisite of oxygen-evolving photosynthesis. For cyanobacteria, phycobilisome (PBS) movement during light state transition has long been expected, but never observed. Here the dynamic behavior of PBS movement during state transition in cyanobacterium Synechocystis PCC6803 is experimentally detected via time-dependent fluorescence fluctuation. Under continuous excitation of PBSs in the intact cells, time-dependent fluorescence fluctuations resemble “damped oscillation” mode, which indicates dynamic searching of a PBS in an “overcorrection” manner for the “balance” position where PSII and PSI are excited equally. Based on the parallel model, it is suggested that the “damped oscillation” fluorescence fluctuation is originated from a collective movement of all the PBSs to find the “balance” position. Based on the continuous fluorescence fluctuation during light state transition and also variety of solar spectra, it may be deduced that light state transition of oxygen-evolution organisms is a natural behavior that occurs daily rather than an artificial phenomenon at extreme light conditions in laboratory. [ABSTRACT FROM AUTHOR]

Probes into the lawsuits that have been filed by U.S. citizens against Japanese corporations since 1999 and examines Congressional legislation and other action taken in direct response to these lawsuits. Selection of bills introduced in the 107th U.S. Congress; Slave labor lawsuits against Japanese multinationals; Slave labor lawsuits in federal and state courts; Related lawsuits against the Japanese government.