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RuNPs stabilised by amino‐decorated imidazolium‐based polymer immobilized ionic liquids catalyse the dimethylamine borane mediated reduction of quinolines to 1,2‐dihydroquinoline (DHQ) and 1,2,3,4‐tetrahydroquinoline (THQ). Partial reduction of 3‐substituted quinolines to the corresponding 1,2‐dihydroquinoline was achieved with 100 % selectivity in toluene under mild conditions. This is the first report of the selective partial reduction of 3‐substituted quinolines to the corresponding 1,2‐dihydroquinolines with a heterogeneous nanoparticle‐based catalyst. A wide range of substituted quinolines have also been reduced to the corresponding 1,2,3,4‐tetrahydroquinoline with high selectivity and good yields by adjusting the reaction time. The 1,2‐dihydroquinolines readily release dihydrogen in toluene at 60 °C in the absence of catalyst with no evidence for disproportionation and as such are potential organo‐hydride reagents. The initial TOF of 610 mol quinoline converted mol Ru−1 h−1 for the reduction of quinoline is among the highest to be reported for a metal nanoparticle‐based catalyst and the conversion of 96 % obtained after 4 h at 65 °C is significantly higher than its platinum nanoparticle counterpart PtNP@NH2‐PEGPIILS as well as 5 wt/% Ru/C, which only reached 9 % and 11 % conversion, respectively, at the same time. Hot filtration experiments showed that the active species was heterogeneous. [ABSTRACT FROM AUTHOR]

Platinum nanoparticles stabilized by imidazolium‐based phosphine‐decorated Polymer Immobilized Ionic Liquids (PPh2‐PIIL) catalyze the hydrolytic evolution of hydrogen from sodium borohydride with remarkable efficiency, under mild conditions. The composition of the polymer influences efficiency with the catalyst based on a polyethylene glycol modified imidazolium monomer (PtNP@PPh2‐PEGPIILS) more active than its N‐alkylated counterpart (PtNP@PPh2‐N‐decylPIILS). The maximum initial TOF of 169 moleH2.molcat−1.min−1 obtained at 30 °C with a catalyst loading of 0.08 mol% is among the highest to be reported for the aqueous phase hydrolysis of sodium borohydride catalyzed by a PtNP‐based system. Kinetic studies revealed that the apparent activation energy (Ea) of 23.9 kJ mol−1 for the hydrolysis of NaBH4 catalyzed by PtNP@PPh2‐PEGPIILS is significantly lower than that of 35.6 kJ mol−1 for PtNP@PPh2‐N‐decylPIILS. Primary kinetic isotope effects kH/kD of 1.8 and 2.1 obtained with PtNP@PPh2‐PEGPIILS and PtNP@PPh2‐N‐decylPIILS, respectively, for the hydrolysis with D2O support a mechanism involving rate determining oxidative addition or σ‐bond metathesis of the O−H bond. Catalyst stability and reuse studies showed that PtNP@PPh2‐PEGPIILS retained 70 % of its activity across five runs; the gradual drop in conversion appears to be due to poisoning of the catalyst by the accumulated metaborate product as well as the increased viscosity of the reaction mixture. [ABSTRACT FROM AUTHOR]

Propane dehydrogenation (PDH) catalyzed by PtSn/Al2O3 is a vital industrial process for producing propylene, a significant building block in the chemical industry. However, coke produced in the process deactivates the catalyst and the energy‐intensive regeneration procedures can produce considerable CO2 emission. In this work, coke on the spent catalysts is analyzed by thermogravimetric‐mass spectra, Raman spectra, 1H solid NMR spectra, and infrared spectra. Several C3 species, including propyl, propylidene and propylidyne are found on the surface of the PtSn alloy. Several reaction pathways are investigated by density functional theory (DFT) calculations. It is also found that this coke can be hydrogenated to propylene in the PDH process. These results could provide theoretical guidance for optimizing process parameters in industry. [ABSTRACT FROM AUTHOR]

A high-linearity input-buffer with high output common-mode stability for 10-bit 3.2 GS/s ADC is proposed in this Letter. The buffer is mainly composed of a source follower for strong driving ability. To enhance its linearity, a feed forward signal path from input to output is proposed. A replica buffer-based common-mode feedback is designed to achieve high output common-mode stabilisation of input-buffer. The prototype is implemented in 40 nm CMOS process. The output common-mode variation is reduced from 200 to 1 mV. Input-buffer consumes 96 mW in 3.2 GHz sampling rate and achieves 69.3 dB spur-free dynamic range at 1581 MHz input frequency. [ABSTRACT FROM AUTHOR]

A novel group‐delay‐insensitive linear equaliser (GDILE) is proposed to reduce the eye‐skew in four‐level pulse amplitude modulation (PAM‐4) receivers. With a cross‐coupled positive‐feedback degeneration network, the proposed GDILE employs additional pole and zero into its transfer function to reduce the group‐delay variation with frequency. Simulation results shows a 40 Gbit/s PAM‐4 receiver that employs a GDILE that can reduce the eye‐skew by 73% compared with the conventional linear equaliser with a modest increase of power consumption. [ABSTRACT FROM AUTHOR]

To address the limited linearity range of current‐mode logic circuits used for four‐level pulse amplitude modulation (PAM‐4) symbol generation, a voltage‐mode, inverter‐like circuit featuring a stacked transistor–resistor structure is proposed. Simulation results have shown that the linearity of the proposed PAM‐4 circuit has been improved by 43.1%, with a modest increase of circuit area. Additionally, 20% resistance mismatch in the proposed PAM‐4 symbol generator leads to linearity degradation of <9%. [ABSTRACT FROM AUTHOR]

To reduce pattern‐dependent jitter in four‐level pulse‐amplitude modulation (PAM‐4) signalling, a transition‐aware feed‐forward equaliser (TFFE) is proposed. By allowing the transition time to vary according to the transition types of the PAM‐4 symbols, switching jitter in TFFE‐based PAM‐4 transmitters can be greatly suppressed, down to the non‐return‐to‐zero (NRZ) level. Simulation results confirm that a PAM‐4 transmitter that employs a TFFE can reduce the jitter level by 0.18 unit interval peak‐to‐peak, and this proposed equaliser can achieve nearly identical eye height as the conventional PAM‐4 feed‐forward equalisers design without introducing any signal‐to‐noise ratio penalty. [ABSTRACT FROM AUTHOR]

A real‐time temperature detection circuit with 0.1°C accuracy is presented. The temperature sensor is composed by a current controlled oscillator (ICO). Its oscillating frequency is proportional to the temperature but independent with the power supply. The frequency change will be digitised by a counter and thus realise the temperature detection. The detection accuracy is limited by the linearity of ICO. In order to improve temperature detection accuracy, a temperature segmentation algorithm is proposed. The temperature sensor is implemented with 0.18 μm CMOS technology and the core area is 0.023 mm2. The power consumption of the proposed sensor is 0.3 mW with 1.8 V supply. Experimental results show that this sensor can detect the temperature from −40 to 125°C with 0.1°C accuracy and the detection error is within ±0.8°C. [ABSTRACT FROM AUTHOR]