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Although evidence of hydrological responses to climate is abundant, changes in water yield (WY) in mountainous regions due to climate change and intensified cryospheric melt remain unclear, mainly because of limited observations and large uncertainties in cryosphere-hydrological modeling. In this study, we used annual runoff observations and a high-resolution precipitation dataset to examine the long-term changes in WY in the Upper Brahmaputra River (UBR) basin, as represented by six sub-basins from the stream head to downstream. We found that WY generally increased during 1982-2013, but regime shifts were detected in the late 1990s. Moreover, the direction of the changes in WY reversed from increasing to decreasing in recent years despite the magnitude of the changes continually increasing from less than 10% to 80.5%. Furthermore, we used the double mass curve technique to assess the effects of climate, vegetation, and the cryosphere on WY. The results showed that the climate and cryosphere together contributed to over 80% of the magnitude increases in WY over the entire UBR basin. However, the combined effects were either offsetting or additive, further leading to slight or substantial magnitude increases, respectively, in which the role of vegetation was nearly negligible. Nevertheless, we found that meltwater from the cryosphere had the potential to alleviate the loss of water availability, which mainly resulted from reduced effective precipitation in most regions. Therefore, the combined effects of climate and cryosphere changes should be considered in ecological restoration and water resources management, particularly involving co-benefits for upstream and downstream regions. [ABSTRACT FROM AUTHOR]

This paper proposes a novel multi‐mode bulk acoustic wave (BAW) coupled resonator filter (CRF) for wideband applications. Three stepped‐impedance coupling layers of CRF are used to generate multi‐mode properties, and external inductors are added for port match. To facilitate the calculation of resonance frequencies, a simplified Mason model is derived and applied in the even‐ and odd‐mode analysis of CRF. Based on different acoustical length of CRF coupling layers, four cases that are applicable for different filter bandwidth are proposed. From these cases, fractional bandwidth (FBW) of the multi‐mode CRF can be realized in a wide range from 12.8% to 33% when the coupling layers adopt the commonly used SiO2/Mo/SiO2 materials. Moreover, the tuning range of FBW can be further enlarged by changing the materials of coupling layers. To verify the proposed multi‐mode CRF, a triple‐mode n77 band filter with center frequency of 3.723 GHz and FBW of 24.2%, and a penta‐mode filter with a larger FBW up to 33% are designed and simulated. Simulation results of the original Mason model, the simplified Mason model, and the three‐dimensional (3D) model based on the finite element method are consistent well with each other. [ABSTRACT FROM AUTHOR]

A low power consumption Amplitude Shift Keying (ASK) modulator employing current reuse cross‐coupled (CRC) LC‐VCO topology and direct injection locking (IL) technique at 10.5‐GHz frequency is presented in this paper. The modulator consumes 864 μW with a DC supply of 1.2 V drawing an average current of 720 μA. The differential VCO is composed of a PMOS‐NMOS pair in stacked series cross‐coupled connection enabling current reuse which results in reduction of the average current drawn from the power source. For comparison, the ASK modulator is also realized with conventional cross‐coupled (CC) topology using NMOS pair. Both circuit approaches are carried out in GF 130‐nm CMOS technology and the post‐layout simulation results of 0.5 × 0.5 mm2 integrated circuits (ICs) show that the CRC topology consumes less power and half of the average current compared to CC topology. Owing to low power requirements, the CRC ASK modulator can be used in self‐powered active Radio Frequency Identification (RFID) tag transmitters for higher data rates. [ABSTRACT FROM AUTHOR]

To improve both thermal stability and friction durability of flexible electronic films with nano‐Ag, a series of flexible films with dendric nano‐Ag embedded into high thermally stable 2‐adamantane containing poly(aryl ether ketone) (2‐ADMPEK, PAEK) substrates are prepared in this work. These films are named as PAEK‐dnAg. The dendric nanostructure of Ag conductive layer performs excellent conductivity with sheet resistance as low as 0.3959 Ω ◻−1. The wide‐angle X‐ray diffraction and scanning electron microscope (SEM) results show dendric nano‐Ag layer well incorporated to PAEK substrates. The results of thermal stability, hydrolysis–oxidation test, adhesion test, and friction durability indicate the PAEK substrate can effectively protect dendric nanosilver conductive layer from heat, harsh oxidation, and friction. The SEM images further show the dendric embedded structure can remain almost unchanged after high temperature (400 °C) heating in air, water boiling oxidation for 12 h, 2500‐cycle 3M tape peeling test, and harsh friction with sanding paper under 5 N, which should lead to the excellent durability of PAEK‐dnAg samples in harsh condition. Thus, PAEK‐dnAgs may show great potential in flexible electronic films application for harsh condition such as high temperature, hydrothermal environment or high friction. [ABSTRACT FROM AUTHOR]

A pole‐converging X‐band low‐noise amplifier (LNA) using 130 nm CMOS technology is proposed. An on‐chip pole‐converging capacitor CPC is added between the gate and drain node of the common‐gate (CG) stage. The capacitor CPC combines with a noise‐reducing inductor L1 to converge poles into the desired band, which results in a pole‐converging effect and wideband performance. The proposed modified broadband simultaneous noise and input‐matching technique is adopted in triple‐cascode configuration to realize good input matching and a low noise figure (NF). Measurement results exhibit a flat maximum power gain of 17.6 dB from 8 to 12 GHz and a reverse isolation over 60 dB within the desired bandwidth along with an NF ranging from 1.5 to 3.6 dB. The LNA core dissipates 17 mW from 2.4 V supply, and the chip size occupies 1.1 × 0.9 mm2 including all pads. The simulated and measured results show good agreement from 8 to 12 GHz. [ABSTRACT FROM AUTHOR]

Thermoplastic polyamide elastomers (TPAEs) were synthesized using polyamide 6 (PA6) as hard segments and polyethylene glycol (PEG) as soft segments. The prepared TPAEs showed a superior mechanical property and thermal property, which the strength and elongation‐at‐break reached 35.50 ± 3.54 MPa and (316.05 ± 20.58)%, respectively, when the molecular weight of soft segment was 600. Furthermore, crystallization property and microphase separation of TPAEs were also investigated in detail, having a significant influence on the foaming behavior of the obtain elastomers. Owing to the restriction of crystalline hard segments, only a few cells formed in the amorphous soft segment regions at foaming temperature of 140°C, while it transformed to larger cells with a thin cell wall at foaming temperature of 160°C and above. When the molecular weight of soft segment increased from 300 to 1000, the average cell size of the foamed TPAEs at 160°C enlarged from 28.73 to 42.17 μm, while the cell density decreased from 5.26 × 108 #/cm3 to 4.25 × 108 #/cm3, both expansion ratio and shrinkage ratio increased gradually. [ABSTRACT FROM AUTHOR]

The authors propose a 4 × 4 circularly polarized (CP) antenna array with wide impedance bandwidth and axial‐ratio (AR) bandwidth and design the same for 60‐GHz applications. The overall structure of the proposed antenna array consists of a cavity‐back circular patch array and two layer feed‐networks. The upper feed‐network is with four TE340 high‐order mode substrate integrated cavities (SIC). Fed with SIC, circular patches with a pair of 42°‐inclined slits can achieve circular polarization. In order to improve the AR bandwidth and gain performance, the substrate integrated waveguide (SIW) sequential rotation feeding technique is utilized in the lower feed‐network. For proof of concept, the 4 × 4 array is fabricated and measured. Measured results show that −10‐dB impedance bandwidth of the proposed antenna array is 27.2% from 52 to 68.4 GHz and 3‐dB AR bandwidth is 18.9% from 55.7 to 67.3 GHz. Furthermore, the 3‐dB gain bandwidth is 26.2% from 53 to 69 GHz with a peak gain reaching 19.3 dBic at 62 GHz. [ABSTRACT FROM AUTHOR]

A power amplifier with bandwidth expansion and linearity enhancement in 130 nm complementary metal‐oxide‐semiconductor (CMOS) process is presented. A LC connected dual‐resonant network is proposed to achieve good broadband performance and high out‐band rejection capability simultaneously. Furthermore, the advanced multiple‐gated transistor technique is employed to cancel out odd‐order intermodulation and harmonic distortions. The PA is implemented in 130 nm CMOS process with an area of 1.17 mm × 0.92 mm. Measurement results demonstrate that the PA exhibits a peak power gain of 8 dB with a relative bandwidth of 38% while maintaining a low reflection coefficient of −23.2 dB, maximum saturation output power of 15.6 dBm, maximum OP1dB and OIP3 of 14.3 dBm and 19 dBm, and a peak power added efficiency of 21.3%, respectively. In addition, an out‐band rejection of 20 dB and 23.2 dB at 6.1 GHz and 14 GHz are measured. [ABSTRACT FROM AUTHOR]

Ultra-sensitive LFA methods for pathogen detection commonly depended on tedious and time-consuming nucleic acid amplification. Here, a high affinity multivalent aptamer (multi-Apt) for S. aureus was obtained through exquisite engineering design. The scaffold and conformation of the multi-Apt were found to be key factors in the detection signal of aptsensors. After optimization, the binding affinity of the multi-Apt to S. aureus was improved by more than 8-fold from 135.9 nM to 16.77 nM. By the joint use of the multi-Apt and a multifunctional nanozyme Fe 3 O 4 @MOF@PtPd, a fast and ultra-sensitive LFA for S. aureus was developed (termed MA-MN LFA). In this method, a Fe 3 O 4 @MOF@PtPd nanozyme was modified with vancomycin and could efficiently capture and separate S. aureus. Moreover, the multi-Apt worked together with the nanozyme to bind with S. aureus to form a ternary complex at the same time, which simply the fabrication of LFA strip. The developed MA-MN LFA could detect S. aureus as low as 2 CFU/mL within 30 min and a wide linear range of 10–1 × 108 CFU/mL was obtained. The detection is easily operated, fast (can be completed within 30 min) and versatile for Gram-positive pathogens, thus has great potential as a powerful tool in pathogen detection. [Display omitted] [ABSTRACT FROM AUTHOR]