Rural biomass energy 2020: People's Republic of China

The developing world is looking for effective, creative ideas for upscaling clean, renewable energy. No place will gain more socially, economically, and environmentally from increased access to clean, reliable energy than poor, rural areas. Biomass energy, produced from animal and crop wastes, is a sensible renewable energy option for rural areas and it can be cost-effective at community and industry scales if guided effectively by governments. This publication explores the potential of biomass energy to close the urban–rural energy gap, raise farmer incomes, and mend the environment in the People’s Republic of China (PRC). Its findings are instructive for other developing and medium-income countries exploring energy-for-all strategies. The report examines the promises and limitations of leading biomass energy technologies and resources for various distribution scales, including but not limited to household biogas digesters. The information is based on lessons learned and experiences from the Asian Development Bank–financed Efficient Utilization of Agricultural Wastes Project in the PRC, as well as findings and conclusions from a technical assistance grant to assist the government draft a national strategy for developing rural biomass energy.rural biomass energy; rural development; biomass resources; biomass technologies; China

Design of Dispersive Delay Structures (DDSs) Formed by Coupled C-Sections Using Predistortion with Space Mapping

The concept of space mapping is applied, for the first time, to the design of microwave dispersive delay structures (DDSs). DDSs are components providing specified group delay versus frequency responses for real-time radio systems. The DDSs considered in this paper are formed by cascaded coupled C-sections. It is first shown that aggressive space mapping does not provide sufficient accuracy in the synthesis of DDSs. To address this issue, we propose a predistortion space mapping technique. Compared to aggressive space mapping, this technique provides enhanced accuracy, while compared to output space mapping, it provides greater implementation simplicity. Two full-wave and one experimental examples are provided to illustrate the proposed predistortion space mapping technique

Shaping Metallic Nanoparticles Toward Integrated Plasmonics and Catalysis

Noble metal nanoparticles have been of tremendous interest because of their intriguing size- and shape-dependent plasmonic and catalytic properties. The combination of tunable plasmon resonances with superior catalytic activities on the same nanoparticle, however, has long been challenging because plasmonics and catalysis require nanoparticles in two drastically different size regimes. Tunable plasmon resonances is a unique feature of sub-wavelength metallic nanoparticles, whereas heterogeneous catalysis requires the use of sub-5 nm nanoparticles as the catalysts. In this dissertation, I firstly found a unique way to bridge this size gap between nanoplasmonics and nanocatalysis. I demonstrated that desired plasmonic and catalytic properties can be integrated on the same particle by controllably creating high energy facets on individual sub-wavelength metallic nanoparticles, such as, porous Au nanoparticles, Au nanocrystals enclosed by well-defined high-index facets, multi-faceted Au and bimetallic nanorods. The capabilities to both nanoengineer high energy facets and fine-tune the plasmon resonances through deliberate particle geometry control allow us to use these nanoparticles for a dual purpose: as substrates for plasmon-enhanced spectroscopies and efficient surface catalysts. Such dual functionality enables us to gain quantitative insights into the facet-dependent molecular transformations on metallic nanocatalysts using surface-enhanced Raman spectroscopy (SERS) as an ultrasensitive spectroscopic tool with unique time-resolving and molecular finger-printing capabilities. More recently, I further expanded my research interest into plasmonic hot electron-driven photocatalytic reactions. I focused on the quantitative understanding of the kinetics and underlying pathways of plasmon-driven photocatalysis. I used SERS to precisely monitor, in real time, the plasmon-driven photoreaction kinetics at the molecule-nanoparticle interfaces. The reductive dimerization of 4-nitrothiophenol and oxidative coupling of thiophenol-derivates were chosen as model reactions to explore the effects of plasmon excitations, molecular adsorption states, local field enhancements, and photothermal processes, on the plasmon-driven photocatalytic reactions. In summary, the goal of this dissertation is to gain new insights on interfacial molecular transformation kinetics and underlying mechanism of heterogeneous catalysis and plasmon-driven photocatalysis using in situ plasmon-enhanced spectroscopic tool for guiding rational design of high performance metallic nanocatalysts and photocatalysts toward environmental and energy application

Enhanced Bandwidth and Diversity in Real-Time Analog Signal Processing (R-ASP) using Nonuniform C-section Phasers

We show that a continuously nonuniform coupled line C-section phaser, as the limiting case of the step discontinuous coupled-line multisection commensurate and non-commensurate phasers, provides enhanced bandwidth and diversity in real-time analog signal processing (R-ASP). The phenomenology of the component is explained in comparison with the step-discontinuous using multiple-reflection theory and a simple synthesis procedure is provided. The bandwidth enhancement results from the suppression of spurious group delay harmonics or quasi-harmonics, while the diversity enhancement results from the greater level of freedom provided by the continuous nature of the nonuniform profile of the phaser. These statements are supported by theoretical and experimental results