The first (3 + 2)/(3 + 2) sequential annulation of γ-vinyl allenoates with alkylidenemalononitriles enabled by phosphine catalysis has been reported. A broad range of structurally dense tetra- and penta-substituted bicyclic­[3,3,0]­octene derivatives, containing a quaternary center and three sequential stereogenic center, were synthesized in good to excellent yields. In this approach, three new C–C bonds are formed in one pot, and εC and αC of γ-vinyl allenoate are two electrophilic centers, whereas its γC exhibits nucleophilic reactivity.

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The presented analog front end (AFE) used to process human bio-signals consists of chopping instrument amplifier (IA), chopping spikes filter and programmable gain and bandwidth amplifier. The capacitor-coupling input of AFE can reject the DC electrode offset. The power consumption of current-feedback based IA is reduced by adopting capacitor divider in the input and feedback network. Besides, IA's input thermal noise is decreased by utilizing complementary CMOS input pairs which can offer higher transconductance. Fabricated in Global Foundry 0.35 μm CMOS technology, the chip consumes 3.96 μA from 3.3 V supply. The measured input noise is 0.85 μVrms (0.5–100 Hz) and the achieved noise efficient factor is 6.48.

A portable, real-time, wireless indoor air monitoring system is designed using the Arduino Yun platform. Because of the importance of a clean indoor environment on human health, the proposed prototype is designed to monitor the temperature, humidity, volatile organic compounds (VOCs) and miniature dust particles. The Arduino Yun platform incorporates an MCU that acquires and sends the data to a Wi-Fi chipset, serving as the communication bridge between the server and clients. Experimental results shows that temperature, humidity, concentration of VOCs and dust particle density can be detected in household with acceptable sensitivities, up to 50m away wirelessly, and charted in real-time with a HTML-5.0 enabled web browser. At the same time, all the historical data are stored in cloud.

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