We report here a chemical sensor based on detecting the mechanical response of a thin (approximately 10-microm) polymer wire stretched across the two prongs of a wristwatch quartz tuning fork (QTF). When the fork is set to oscillate, the wire is stretched and compressed by the two prongs. The stretching/compression force changes upon adsorption of analyte molecules onto/into the polymer wire, which is detected by the QTF with pico-Newton force sensitivity. An array of such sensors with different polymer wires is used for simultaneous detection of several analytes and for improvement of pattern recognition. The low cost (approximately 10 cent) of the QTF, together with that an array of QTFs can be driven to oscillate simultaneously and their resonance frequencies detected with the same circuit, promises a high performance, low cost, and portable sensor for detecting various chemical vapors. We demonstrate here detection of parts-per-billion-level water, ethylnitrobenzene, and ethanol vapors using the QTF arrays.

-This paper reports the development and characterization of a novel switching device for use in microwave systems. The device utilizes a switching mechanism based on nanoionics, in which mobile ions within a solid electrolyte undergo an electrochemical process to form and remove a conductive metallic "bridge" to define the change of state.The nanoionics-based switch has demonstrated an insertion loss of ~0.5dB, isolation of >30dB, low voltage operation (1V), low power (~μW) and low energy (~nJ) consumption, and excellent linearity up to 6 GHz. The switch requires fewer bias operations (due to non-volatile nature) and has a simple planar geometry allowing for novel device structures and easy integration into microwave power distribution circuits.

Large-scale production of organic photovoltaics (OPVs) at low cost is, still, a future concept thought to promote the market share of solar energy. Working towards the roll-to-roll production of OPVs, different compatible deposition techniques are investigated. Inkjet printing is a promising candidate, as it allows the contact-free deposition of patterned functional materials with high flexibility. In this article, we further extend the application of inkjet printing for roll-to-roll production of OPVs. Inkjet-printed high-conducting PEDOT:PSS is compatible with indium tin oxide-free devices, by combination with an Ag grid to form the anode. A P3HT/PCBM layer is inkjet printed on top using non-chlorinated halogen-free solvents only, and large-area homogeneous layers with surface areas up to 3 cm by 3 cm were obtained. The device thus manufactured showed performance comparable to a reference device with spin-coated layers for which chlorobenzene was used as solvent for the photoactive layer. This is an essential step forward in the knowledge on materials and process conditions using inkjet printing for OPVs and working towards the full roll-to-roll production of OPVs without loss of performance.

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DMSO).High resolution mass spectrometry (HRMS) analyses were performed with an Agilent LC-MS TOF 1260-6224.Crystallographic data (CCDC number: monomer 1, 1493349; monomer 2, 1474129; compound 4, 1474130; compound 9, 1474925) was collected by the X-ray analysis service at Huazhong Normal University (SMART APEX CCD, monomer 2, 9) or Wuhan University (Bruker SMART APEX2, monomer 1) and cif files are attached.Melting point was recorded on a WRS-2A digital melting point instrument.The Raman spectroscopy measurement was conducted with an Invia Raman spectroscope (λ = 785 nm). Materials were milled between two glass slides and measured directly on a glass slide.For the Infrared (IR) spectra, Materials were mixed with KBr and measured with an Nicolet iS10 Infrared spectroscope.The optical microscopy measurement was performed with a transflective polarized microscope (Shanghai Tuming CP-602C).The differential scanning calorimetry (DSC) spectrometry was measured by Shimadzu DSC-60 under a nitrogen atmosphere.The Thermal Gravimetric Analysis (TGA) was performed with Perkin elmer Diamond TG/DTG under a nitrogen atmosphere.