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Abstract Microorganisms used in syngas fermentation require nutrients to grow and convert syngas (CO, H2 and CO2) into various products. Many of the essential nutrients can be provided by biochar. Poultry litter biochar (PLBC) contains minerals and trace metals and has a high pH buffering capacity, making it suitable as a nutrient supplement. The effects of PLBC loadings from 1 to 20 g L−1 on syngas fermentation were determined in 250 ml bottle assays. Results showed that 10 and 20 g L−1 PLBC significantly increased ethanol production compared to standard yeast extract (YE) medium. Fermentations in a 3L continuous stirred tank reactor (CSTR) with 10 g L−1 PLBC with and without 4-morpholineethanesulfonic acid (MES) showed 64% and 36% more ethanol production, respectively, than standard medium. The acetic acid accumulated at the beginning of fermentation was completely converted to ethanol in all media tested in the CSTR. These results demonstrate the feasibility of using PLBC medium without costly MES in the CSTR to enhance ethanol production from syngas for potential use at commercial scale.

The rapid development of advanced metering infrastructure provides a new data source—building electrical load profiles with high temporal resolution. Electric load profile characterization can generate useful information to enhance building energy modeling and provide metrics to represent patterns and variability of load profiles. Such characterizations can be used to identify changes to building electricity demand due to operations or faulty equipment and controls. In this study, we proposed a two-path approach to analyze high temporal resolution building electrical load profiles: (1) time-domain analysis and (2) frequency-domain analysis. The commonly adopted time-domain analysis can extract and quantify the distribution of key parameters characterizing load shape such as peak-base load ratio and morning rise time, while a frequency-domain analysis can identify major periodic fluctuations and quantify load variability. We implemented and evaluated both paths using whole-year 15-minute interval smart meter data of 188 commercial office building in Northern California. The results from these two paths are consistent with each other and complementary to represent full dynamics of load profiles. The time- and frequency-domain analyses can be used to enhance building energy modeling by: (1) providing more realistic assumptions about building operation schedules, and (2) validating the simulated electric load profiles using the developed variability metrics against the real building load data.

Abstract To obtain high yield and high concentration glucose from corncob residues (CRs), tetrahydrofuran (THF) + H2O co-solvent pretreatment was employed. The pretreatment parameters were firstly optimized by Box-Behnken Design of response surface method, and the maximum glucose yield (498.2 mg/g CRs) was obtained via enzymatic hydrolysis after pretreated under optimized conditions (53.7% THF concentration, 202.3 °C, 1.05 h). Then, the pretreated CRs under optimized conditions (optimized-CRs) were enzymatically hydrolyzed at high solid loading (15%–20%) and low enzyme input (5–8 FPU/g cellulose). The high concentration glucose production (128.6 mg/mL) was obtained from optimized-CRs after enzymatic hydrolysis at 20% solid loading with 10 FPU/g cellulose for 72 h, and then showed potential for reduction of enzyme input. Finally, the interactions between the 9 substrate-related factors and cellulose conversion were analyzed through correlation analysis, and found that Klason lignin remained in the cellulose-rich fractions and pseudo lignin condensed on the surface of the recovered substrate were the predominant inhibitors for enzymatic hydrolysis.

Abstract The prime purpose of this work is to prepare a novel kind of Pickering interfacial solid catalysts for biodiesel production to meet the requirements of highly efficiency and environmental benign. To achieve this goal, the core–shell P[xSPA-yDABCO]@SiO2@Fe3O4 composite materials with a shell of photo-responsive and base catalytic sites were manufactured by means of layer-by-layer fabrication method. The modified materials, entirely characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectra, X-ray powder diffraction (XRD) and magnetization versus magnetic (VSM) techniques, demonstrated sufficient catalytic active sites and photo-responsive sites. Among all the so-prepared catalysts, P[3SPA-2DABCO]@SiO2@Fe3O4 performs extremely well and can stabilize soybean oil-in-methanol Pickering emulsion for 24 h, achieving a biodiesel yield up to 98.2% at a catalyst dosage of 5 wt% after the reaction time of 5 h at 60 °C. Furthermore, the double responsive solid catalyst can be readily separated from the mixture of reaction by an external magnet and UV irradiation, and still presented superior catalytic activity after 6 cycles.

Ancillary services and other interconnected services are important especially in a competitive operation environment. Since these services are costs related, they should be allocated in order to send the correct price signal to market participants. An average sensitivity method is proposed for allocating services to simultaneous transactions. It can provide results close to power flow-based methods, while requiring as little computational time as traditional sensitivity-based approaches. Except for rare cases, it satisfies the requirement of allocation quantity, allocation ratio, and application feasibility. Test results indicate that the average sensitivity method is a successful allocation algorithm.

The electro-hydraulic servo pump control system (EHSPCS) is a volume control system that uses a permanent magnet synchronous motor (PMSM) with a fixed displacement pump to directly drive and control the hydraulic cylinder. The energy transmission law of the system is very complicated due to the transformation of electrical, mechanical and hydraulic energy as well as other energy fields, and qualitative analysis of the energy transfer efficiency is difficult. Energy transfer analysis of the EHSPCS under different working conditions and loads is proposed in this paper. First, the energy flow transfer mechanism was analyzed, and the mathematical and energy transfer models of the key components of the system were established to explore the energy characteristic state transition rule. Second, a power bond diagram model was built, its state equation and state matrix were deduced, and a system simulation model was built. Finally, combined with the EHSPCS experimental platform, simulation experiments were carried out on the dynamic position following and steady-state position holding conditions of the system, and the variation rules of the power of each energy characteristic state and the system energy transfer efficiency under different loads were obtained. The research results provide a foundation for the study of power matching and energy-saving mechanism of the EHSPCS.