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Ozone (O 3) addition combustion is a trending technique to enhance the ignition characteristics of hydrocarbon fuel. In this study, the spray ignition characteristics of jet fuel along with hydrogen (H 2) and O 3 seeding were experimentally investigated and numerically simulated with an updated chemical kinetic model. The ignition delay (ID) period of jet propellant 5 (JP-5) with H 2 /O 3 addition was measured using a constant volume combustion chamber (CVCC) at 600 K to 818 k, the pressure of 15 bar, equivalence ratio of 0.5. The intake manifold was added with air, H 2 (10%, and 20% volume fraction), and 2000 ppm ozone (O 3). In general, pure JP-5 has a shorter ID than those obtained with H 2 addition. At 600 K, with 10% and 20% H 2 to JP-5, the ID was increased by 18.49%, and 35.12% respectively. When O 3 was added, the ID of JP-5 was shortened by 10%, while for 10% and 20% H 2 addition, the ID was shortened by 19.25% and 22.5%, respectively. An existing jet fuel mechanism was chosen and validated with the previous and the present study experimental ID. The model was in agreement with the practical ID. The H 2 -mechanism rate constants were updated with the recently optimized values available in the literature to reflect the newly obtained experimental data at low temperatures. An existing sub-mechanism of O 3 was adopted and combined with the JP-5 model. The updated model was validated with the present study ID data. Good predictions were noticed between the model and JP-5 experimental ID. However, a small deviation of 5.01% and 0.71% was found for 10%, and 20% H 2 ID at 600 K. The reaction H 2 + OH = H 2 O + H and HO 2 + HO 2 = H 2 O 2 + O 2 were found to be the critical reactions responsible to reduce the systems reactivity and makes the fuels ID to become longer. The O-atom from O 3 was decomposed through the reaction O 3 + N 2 = O 2 + O + N 2 , and O 3 + O 2 = O 2 + O + O 2 at an early stage of combustion. Due to H 2 addition to O 3 and air, the early formation of OH radicals is due to O 3 + H = O 2 + OH, which further accelerates the oxidation of the fuel, resulting in a shorter ID. [ABSTRACT FROM AUTHOR]

A simple, low-temperature hydrothermal method and atomic layer deposition (ALD) were used to fabricate ZnO nanostructures as subwavelength-structure antireflection layers (SWS ARLs) on Si solar cells. ZnO seed layers with wafer-scale uniformity were prepared, and ALD was used to reproduce two types of ZnO-based structures, nanorod arrays (NRAs) and nanotip arrays (NTAs). The study examined diammonium phosphate concentrations during growth, conducted simulations based on three-dimensional finite-difference time-domain and reflection analyses, performed X-ray diffractometer, field-emission scanning electron microscope, and high-resolution transmission electron microscope characterizations, measured total reflectance spectra by using a spectrophotometer with integrated spheres, and ran solar simulations to determine the efficiency of the Si solar cells. Coating the ZnO NTAs on the Si solar cells yielded a low total reflectance over a broad band range and produced omnidirectional light scattering on the cells, causing incident light to have a shallow penetration depth near the p–n junction and leading to an increase in short current density ( Jsc ). Coating the ZnO NTAs with an Al 2 O 3 shell induced continuous variation in the refractive index, further decreasing the total reflectance to approximately 5.5%, and protected the ZnO NTAs from the harmful acidic environment. Significantly increasing the J sc and η levels of the Si solar cells, the Al 2 O 3 @ZnO-NTA antireflection structure produced a high efficiency of 17.79%. Its superior performance, including low and wideband reflectance, a low process temperature, and a significant increase in efficiency, indicates the potential of this antireflective structure for enhancing solar cell efficiency in photovoltaic devices. [ABSTRACT FROM AUTHOR]

HRJ (Hydro-processed Renewable Jet) conversion technology has been recently used to produce renewable jet fuel for commercial or military flights. In this study, a techno-economic analysis is carried out for evaluating the production of jatropha-derived HRJ fuel through a bio-refinery process. Each component of the chosen feedstock jatropha can be converted into valuable products. The bio-refinery process is split into 6 parts: (1) Fruit Dehulling; (2) Shell Combustion; (3) Oil Extraction; (4) Press Cake Pyrolysis; (5) Oil Upgrading; (6) Product Separation. The minimum jet fuel selling price (MJSP) from this fruit scenario is calculated to be $5.42/gal based on the plant capacity of 2400 metric tonne of feedstock per day. The co-products obtained from the process not only significantly deduct the production cost but make the entire process energy self-sustainable. We also discuss the oil scenario, which oil is the starting material and the process begins from Oil Upgrading section. The oil scenario offers the MJSP of $5.74/gal with lower capital but higher operating costs. The differences of MJSPs for fruit and oil scenarios are due to feedstock cost, refinery capital cost, co-product credits and energy cost. Based on the sensitivity analysis, the feedstock price, oil content, plant capacity, reactor construction and catalyst usage are important parameters that control the price of the produced fuel. [ABSTRACT FROM AUTHOR]

Background and objective In this study, we developed a computer controlled treadmill system using a recurrent fuzzy neural network heart rate controller (RFNNHRC). Treadmill speeds and inclines were controlled by corresponding control servo motors. The RFNNHRC was used to generate the control signals to automatically control treadmill speed and incline to minimize the user heart rate deviations from a preset profile. Methods The RFNNHRC combines a fuzzy reasoning capability to accommodate uncertain information and an artificial recurrent neural network learning process that corrects for treadmill system nonlinearities and uncertainties. Treadmill speeds and inclines are controlled by the RFNNHRC to achieve minimal heart rate deviation from a pre-set profile using adjustable parameters and an on-line learning algorithm that provides robust performance against parameter variations. The on-line learning algorithm of RFNNHRC was developed and implemented using a dsPIC 30F4011 DSP. Results Application of the proposed control scheme to heart rate responses of runners resulted in smaller fluctuations than those produced by using proportional integra control, and treadmill speeds and inclines were smoother. The present experiments demonstrate improved heart rate tracking performance with the proposed control scheme. Conclusions The RFNNHRC scheme with adjustable parameters and an on-line learning algorithm was applied to a computer controlled treadmill system with heart rate control during treadmill exercise. Novel RFNNHRC structure and controller stability analyses were introduced. The RFNNHRC were tuned using a Lyapunov function to ensure system stability. The superior heart rate control with the proposed RFNNHRC scheme was demonstrated with various pre-set heart rates. [ABSTRACT FROM AUTHOR]

The purpose of the present study is to develop a small-scale horizontal-axis wind turbine (HAWT) suitable for the local wind conditions of Tainan, Taiwan. The wind energy potential was first determined through the Weibull wind speed distribution and then was adapted to the design of the turbine blade. Two numerical approaches were adopted in the design and analysis of the HAWT turbine blades. The blade element momentum theory (BEMT) was used to lay out the shape of the turbine blades (S822 and S823 airfoils). The geometry of the root region of the turbine blade was then modified to facilitate integration with a pitch control system. A mathematical model for the prediction of aerodynamic performance of the S822 and S823 airfoils, in which the lift and drag coefficients are calculated using BEMT equations, was then developed. Finally, computational fluid dynamics (CFD) was used to examine the aerodynamic characteristics of the resulting turbine blades. The resulting aerodynamic performance curves obtained from CFD simulation are in agreement with those obtained using BEMT. It is also observed that separation flow occurred at the turbine blade root at the tip speed ratios of 5 and 7. [ABSTRACT FROM AUTHOR]

Biomass-derived jet (bio-jet) fuel has become a key element in the aviation industry׳s strategy to reduce operating costs and environmental impacts. Researchers from the oil-refining industry, the aviation industry, government, biofuel companies, agricultural organizations, and academia are working toward developing a commercially viable and sustainable process that produces a long-lasting renewable jet fuel with low production costs and low greenhouse emissions. This jet fuel, additionally, must meet ASTM International specifications and potentially be a 100% drop-in replacement for current petroleum jet fuel. In this study, the current technologies for producing renewable jet fuels, categorized by alcohols-to-jet, oil-to-jet, syngas-to-jet, and sugar-to-jet pathways are reviewed. The main challenges for each technology pathway, including conceptual process design, process economics and life-cycle assessment of greenhouse gas emissions are discussed. Although the feedstock price and availability and energy intensity of the process are significant barriers, biomass-derived jet fuel has the potential to replace a significant portion of conventional jet fuel required to meet commercial and military demand. [ABSTRACT FROM AUTHOR]

• An RCM is developed to study jet fuel ignitions at low-to-intermediate temperature. • High H/C and low cyclic molecules improve the fuel reactivity. • Double compression pressure shortens the ignition delay by 59 % The combustion characteristics of jet fuels, including conventional (Jet-A1 and JP-5) and renewable (hydro-processed renewable jet, HRJ) jet fuels at low-to-intermediate temperatures were studied in a rapid compression machine (RCM). Compression pressures were varied at 10, 15, and 20 bar under a low temperature combustion regime (626 K-874 K). Fuel/oxidizer mixture conditions were created in order to investigate the auto-ignition delays responding to various equivalence ratios of 0.25 and 0.5. Longer auto-ignition delays were observed with a leaner fuel/oxidizer mixture (ϕ = 0.25) by as much as 79.2% as compared to the richer mixture condition (ϕ = 0.5). Doubling the compression pressures from 10 to 20 bar led to the reduction of the auto-ignition delays by as much as 58.8%. The negative temperature coefficient (NTC) regime was found to be strongly related to the changes in the equivalence ratio, where the NTC formation is clearly observed at lower equivalence ratio of 0.25 for all the tested fuels. In addition, the renewable jet fuel exhibited a shorter auto-ignition delay by as much as 54.5% as compared to Jet-A1 and JP-5 at equivalence ratio of 0.5. The higher hydrogen-to-carbon (H/C) ratio and lower concentration of cyclic molecules in the HRJ were among the reasons for the reactivity improvement compared to the petroleum jet fuels. [ABSTRACT FROM AUTHOR]

Porcine circovirus-associated disease is a highly contagious disease that has significant economic consequences. The disease is prevalent in many countries and regions. To generate a genetic marker strain of PCV2, a Sal I restriction enzyme site was inserted into the PCV2 clone as a genetic marker by applying iDNA infectious clone technology. The iDNA represents plasmids that encode the full-length DNA genome of PCV2 assembled in a pcDNA3.1-based vectors. The mutant PCV2 was rescued by transfecting an infectious clone into PK-15 cells and was characterised by an immunoperoxidase monolayer assay (IPMA). The viral genome could be differentiated from the wild-type parent by PCR and restriction fragment length polymorphism (PCR-RFLP). Kunming mice were inoculated with the PCV2 infectious clone or rescued virus via intranasal and intraperitoneal routes. Seroconversion to PCV2-specific antibody appeared in the majority of mice from the two inoculated groups at 7 days postinoculation (DPI), and the specific antibody level was steady for at least 42 days. Viraemia, beginning at 7 DPI and lasting 4 weeks, was detected in the majority of the pigs from the two inoculated groups. The animal experiments revealed that the PCV2 infectious clone and rescued virus both could replicate in mice and induce mice to generate anti-PCV2 antibodies. The infectious clones of PCV2 will be useful for further research investigating a potential tractable iDNA vaccine by reverse genetics technology for attenuated virulance. [ABSTRACT FROM AUTHOR]

The commercial production of jet fuel from camelina oil via hydrolysis, decarboxylation, and reforming was simulated. The refinery was modeled as being close to the farms for reduced camelina transport cost. A refinery with annual nameplate capacity of 76,000 cubic meters hydrocarbons was modeled. Assuming average camelina production conditions and oil extraction modeling from the literature, the cost of oil was 0.31 $ kg −1 . To accommodate one harvest per year, a refinery with 1 year oil storage capacity was designed, with the total refinery costing 283 million dollars in 2014 USD. Assuming co-products are sold at predicted values, the jet fuel break-even selling price was 0.80 $ kg −1 . The model presents baseline technoeconomic data that can be used for more comprehensive financial and risk modeling of camelina jet fuel production. Decarboxylation was compared to the commercially proven hydrotreating process. The model illustrated the importance of refinery location relative to farms and hydrogen production site. [ABSTRACT FROM AUTHOR]

Understanding the mechanisms of catalytic and reactions calls for in situ/operando spectroscopic characterization. Here we report the developments of in situ reaction cells at the Advanced Light Source for soft X-ray spectroscopic studies of nanoparticle catalysts during the catalytic reactions. The operation of these various cells and their capabilities are illustrated with examples from the studies of Co-based nanocatalysts. [ABSTRACT FROM AUTHOR]

Hydroprocessed renewable diesel was produced using a hydro-treatment technology that is mainly dependent on the feedstock quality and catalyst performance. In this study, the regeneration of NiMo/γ-Al 2 O 3 hydroprocessing catalyst was investigated with continuous and batch operations for the purpose of recovering waste catalyst and improving catalyst performance. Supercritical carbon dioxide and co-solvent were utilized to perform the regeneration process, and the process parameters were discussed. Furthermore, the regenerated catalyst was characterized using TGA, FTIR, BET, and XRD methods and compared to both fresh and spent catalysts. It was found that the optimal regeneration for catalyst could be obtained using a batch mode at the pressure of 76 bar and the temperature of 523 K with injecting 10 mL per period hexane co-solvent for 3 periods, resulting in 15.5% of mass removal rate. The regenerated catalyst possessed >97% conversion while the fresh one obtained >99%. [Display omitted] • Supercritical carbon dioxide was utilized to regenerate NiMo/γ-Al 2 O 3. • Optimal parameters are 76 bar, 523 K and 10 mL/period hexane co-solvent. • The maximum mass removal rate for catalyst regeneration is 15.5%. [ABSTRACT FROM AUTHOR]