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It was well recognized that the pollutant emissions from real-world residential coal combustion contributed significantly to air pollution and human health, resulting in an urgent need for a better understanding of the pollutant emission factors (EFs) of residential coal combustion. However, field-based researches on residential coal combustion emissions are still limited at this stage. In this study, based on carbon balance method, emission factors (EFs) of CO2 and a series of pollutants, including gaseous pollutants (CO, NOX, CH4, and SO2), particulate matters (PM2.5 and PM10), elemental carbon (EC), organic carbon (OC), and polycyclic aromatic hydrocarbons (PAHs) from residential honeycomb briquette (HB) and coal chunk (CC) combustions were measured in real-world cooking stoves. As a result, apart from SO2, the burning of HB produced much less pollutants than CC. The median of emission reduction ratios estimated from Monte Carlo simulation ranged from 2.4% (SO2) to 98.8% (EC) by replacing CC with HB in residential combustion in Shanxi province in 2012. EFs of CO, PM2.5 and PAHs derived from the present field measurement were around 1–50 times higher than those from laboratory tests; furthermore, larger variations were found in our field measurement compared to that in the laboratory studies. This result called for more field measurements to reduce uncertainties of emission inventory estimations. As for the PAH emissions, particle phase PAHs dominated in both HB and CC burning and PAH emissions from HB burning had lower toxicity than CC combustion. Hence, HB is an ideal substituted fuel compared with CC. Previous studies suggested that PAH isomer ratios of FLA/(FLA+PYR) and IcdP/(IcdP+BghiP) above 0.5 represented source of coal combustion, which did not fit with our study well, indicating PAH isomer ratios might not be valid enough for source apportionment.

Residential solid fuel combustion is a major emission source of PAHs (polycyclic aromatic hydrocarbons) in most developing countries, including China; however, accurate estimates of PAH emissions are often challenged by limited real-world emission factors (EFs) under field conditions, which can hardly be repeated in laboratory-controlled tests. In this study, a series of field measurements was conducted to determine the emissions of 28 PAHs from different fuel-stove combinations. A total of 14 fuel-stove combinations were studied. The total EFs of 28 PAHs (EFPAH28), on the basis of fuel mass, ranged from 20.7 to 535 mg/kg, with relatively lower EFs for coal than for biomass. Biomass burning in gasifier stoves had lower PAH EFs and fewer toxic PAH species than biomass burning in traditional brick stoves. Fuel type was a significant factor affecting PAH emissions, while stove difference had a relatively smaller influence. Much higher EFs were found from these field tests than from the idealized laboratory tests, which indicated significant underestimation in inventories based on the laboratory-based EFs. Biomass and coal had different profiles, with larger intra-fuel variations in coal than those in biomass. Highly variable values of some, though not all, commonly used isomer ratios indicated substantial biases in source apportionment relying on single or simple ratios without correction, and the MCE was found to be significantly corrected with some ratios.

Based on the Labajin Bridge, this paper uses Midas civil finite element software to establish a calculation model for the high-dose continuous rigid frame bridge with qualified CFST stack. Taking the height of the pier, the slope of the laced pier and the steel content of the column and limb as the design parameters, the calculation model of 40 different periods is constructed, and the high-dose continuous rigid frame bridge with qualified concrete-filled steel tube stacks under the rare earthquake The elastic and elastoplastic time-history analysis is carried out. By comparing the displacement and bending moment time-history curves of the control section, it is found that the vibration modes of the two different analysis methods are more consistent. Based on this, the seismic simplification method of the bridge is studied. Using the statistical induction method, the relationship between the control section displacement, the bending moment adjustment coefficient and the structural period is obtained by fitting, and the equivalent elastic method is proposed. The algorithm is verified by different seismic waves, fortification intensity and acceleration peak. The results show that the proposed equivalent elastic method agrees well with the elastoplastic method. The research results can effectively improve the computational efficiency of seismic design, and also provide reference and reference for the seismic design specifications of such structural systems.

The semiconductor manufacturing roadmap which generally follows Moore’s law requires smaller and smaller EPE (Edge Placement Error), and this places stricter requirements on OPC model accuracy, which is mainly limited by metrology errors, pattern coverage and model form. Current metrology errors are mainly related to SEM image noise and measurement difficulty in complex 2D patterns. And traditional model form improvement by adding empirical terms for PEB (Post Exposure Bake), NTD (Negative Tone Development) and PRS (Physical Resist Shrinkage) effects still cannot meet the accuracy spec because other physical and chemical effects are uncaptured. Fitting these effects also requires comprehensive pattern coverage during model calibration. Solely improving model form may overfit the metrology error, which is risky, while solely improving metrology ignores existing model errors: both factors are troublesome for OPC. In this paper, a new metrology (MXP, naming for Metrology of Extreme Performance) and deep learning (Newron, naming for a Deep Convolutional Neural Network model form) integrated solution is proposed, where MXP decreases the metrology errors and provides good pattern coverage with high-volume reliable CD and EP (Edge Placement) gauges, and Newron captures remaining complex physical and chemical effects embedded in high-volume gauges beyond the traditional model. This solution shows overall ~30% prediction accuracy improvement compared to baseline metrology and FEM+ (Focus Exposure Matrix) model flow in N14 NTD process, predicts SEM shape of critical weak points more accurately.

A new monitoring technique, which combines real-time in-situ CCD camera observation and reflectance spectra measurement, has been developed to study the growing and drying processes of evaporation-induced self-assembly (EISA). Evolutions of the reflectance spectrum and CCD camera images both reveal that the entire process of polystyrene (PS) EISA contains three stages: crack-initiation stage (T1), crack-propagation stage (T2), and crack-remained stage (T3). A new phenomenon, the red-shift of stop-band, is observed when the crack begins to propagate in the monitored window of CCD camera. Deformation of colloidal spheres, which mainly results in the increase of volume fraction of spheres, is applied to explain the phenomenon. Moreover, the modified scalar wave approximation (SWA) is utilized to analyze the reflectance spectra, and the fitting results are in good agreement with the evolution of CCD camera images. This new monitoring technique and the analysis method provide a good way to get insight into the growing and drying processes of PS colloidal self-assembly, especially the crack propagation.

We have designed a single thin planar diffractive optical element ( DOE) based on the principle of diffractive optics to simultaneously split and concentrate the incident light into several energy ranges for lateral multijunction solar cells. A prototype with the maximum thickness of 6.95 mu m and 32 quantized levels in depth was fabricated by photolithographic technology. The spectrum-splitting and concentrating performance of the prototype, which were measured quantitatively, show good agreement with the simulation results. As mass production of a DOE can be produced by imprint technology, our design provides a feasible means for low-cost, large-scale, and high-efficiency photovoltaic applications. (C) 2013 Optical Society of America

Two improved algorithms are proposed to extend a diffractive optical element (DOE) to work under the broad spectrum of sunlight. An optimum design has been found for the DOE, with a weighted average optical efficiency of about 6.8% better than that of the previous design. The optimization of designing high optical efficiency DOEs will pave the way for future designs of high-efficiency, low-cost lateral multijunction solar cells based on such a DOE.

Self-assembled photonic structures have been under theoretical and experimental study for decades, whereas previous theories on optical properties were mainly concerned with perfect structure or some certain limited kinds of disordered photonic crystals (PCs), making them unsuitable for characterizing the real self-assembled PCs. In order to improve our understanding of the mechanism of self-assembly and provide more crucial clues to further grow perfect crystals, we extended previous widely used scalar wave approximation (SWA), making it be able to characterize long-range disorder (β) and short-range disorder (α) in PCs synthetically in a simple and effective way. Excellent agreement with in situ observed reflectance of evaporation induced self-assembled colloidal photonic crystals (CPCs) was obtained, demonstrating that the introduction of the parameters α and β in SWA can successfully characterize the disorder in self-assembled CPCs. Furthermore, extended SWA was further used to study the disorder formation in self-assembly, and it was found that during growing stage both β and α drop down, whereas in drying stage β stays nearly unchanged while α increases significantly. It turned out that the growing stage of self-assembly is a stage when the structure transforms from disordered to ordered one, and growth induced disorder mainly arises in drying stage. The results obtained provide an insight into the growth mechanisms of self-assembly and theoretical basis for characterizing optical properties of disordered PCs.

✓ Changes in Ca++-adenosine triphosphatase (ATPase) activity in the plasma membrane of smooth-muscle cells in the basilar arteries of dogs with experimental subarachnoid hemorrhage (SAH) were examined. The study methods included electron microscopic histochemistry and bioassay of the enzyme that exports cytoplasmic Ca++ to extracellular spaces. The Ca++-ATPase activity in the basilar artery increased significantly in response to the application of vasoconstrictive agents (prostaglandin F2α and a phorbol ester), but decreased significantly 24 hours after experimental SAH, inversely with basilar artery contraction. Dogs that had undergone two arterial blood injections (double SAH) exhibited a further decrease in Ca++-ATPase activity as well as persistent contraction of the basilar artery for a longer period (at least 7 days) than was seen in animals with a single arterial blood injection. Bioassay of the enzyme also demonstrated a decrease in vascular Ca++-ATPase activity in dogs subjected to double SAH. These findings suggest that the early occurrence of and long-lasting decrease in Ca++-ATPase activity in dogs with experimental SAH induces a persistent disturbance of Ca++ homeostasis and indicates that damage to the plasma membrane in the cerebral arterial smooth-muscle cells proceeds to myonecrosis after SAH.