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From the perspective of the host country, this paper studies the impact of the construction of overseas economic and trade cooperation zones on the innovation level of countries along “the Belt and Road” based on the national level panel data of 42 countries from 2003 to 2019. The research finds that the construction of cooperation zones has significantly improved the innovation level of countries along “the Belt and Road”, and the national cooperation zones passing the assessment of the Ministry of Commerce have a stronger role in improving the innovation level of the host country. This conclusion is still valid after a variety of robustness tests. The conclusions of this study provide empirical evidence that the overseas economic and trade cooperation zone is a win-win “China” model, and has important reference significance for China to improve the function of the opening platform through the cooperation zone and promote the high-quality development of the “the Belt and Road”.

A high-performance distributed optical fiber sensor based on phase-sensitive optical time-domain reflectometry (Φ-OTDR) for dynamic strain measurement has been proposed. In this newly designed system, ultraweak fiber Bragg gratings (UWFBGs) are sparsely embedded in the sensing fiber. Through an unbalanced 3 × 3 coupler structure, the reflected lights from two adjacent UWFBGs would be mixed with each other and then split into three parts for phase demodulation. Then, a novelty table-look-up scheme is introduced to precisely demodulate the frequency, amplitude, and phase of dynamic strain. Rayleigh back-scattering light is utilized to identify and locate the accurate position of vibration event between two adjacent UWFBGs. The experimental results show that the proposed system is capable of reconstructing the vibration with a linear intensity response of R2 = 0.9986 and a fiber length variation sensitivity of 117 pm/(Hz)1/2. Meanwhile, a wide frequency response band from 50 to 2075 Hz is achieved with high signal-to-noise ratio above 56 dB. [ABSTRACT FROM PUBLISHER]

This paper proposes and demonstrates a phase-sensitive optical time domain reflectometry (Φ-OTDR) sensing system with multi-spatial resolution (MSR) analysis property. With both theoretical analysis and an experiment, the qualitative relationship between spatial resolution (SR), signal-to-noise ratio (SNR) and the length of the vibration region has been revealed, which indicates that choosing a suitable SR to analyze the vibration event can effectively enhance the SNR of a sensing system. The proposed MSR sensing scheme offers a promising solution for the performance optimization of Φ-OTDR sensing systems, which can restore vibration events of different disturbance range with optimum SNR in merely a single measurement while maintaining the same detectable frequency range. [ABSTRACT FROM AUTHOR]

The addition of Moringa oleifera Lam. leaves to the raw material for the co-fermentation was a promising way for the novel uses of Moringa oleifera Lam. leaves and the future trend of the Fuzhuan Brick Tea (FBT) industry. However, the effects of the additions on the chemical components and microbial community of FBT as well as the suitable addition amount were still unknown. Based on the metabolomic and microbiota analysis of Fuzhuan Brick (Moringa oleifera Lam.) Tea (MFBT) with different addition amounts of Moringa oleifera Lam. leaves (0%, 25%, 50%), it was found that MFBT had significantly higher contents of alkaloids, amino acids, lipids, organic acids, quinate, whereas had lower contents of flavonoids and polyphenols than FBT. In addition, Aspergillus and Symbiotaphrina were abundant in MFBT but less present in FBT and showed a higher correlation with bacteria and catechin derivatives, flavone, lipids, organic acids, amino acids, alkaloids, respectively. The addition of other plant materials for the co-fermentation was a promising strategy to enhance the function of final products and promote the development of new products types during the production of FBT. • Moringa oleifera Lam. leaves is a potential material for co-fermentation with FBT. • UPLC-Q-TOF/MS and MiSeq sequencing were powerful tools for the analysis of FBT. • Moringa oleifera Lam. leaves with 25% addition was suggested for MFBT production. • The variation of the chemical composition and microbiota in MFBT was illuminated. [ABSTRACT FROM AUTHOR]