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AbstractTo estimate the life cycle cost of thermal power equipments in engineering, this paper established a comprehensive evaluation model of life cycle cost with the life cycle breakdown and cost breakdown structure. Based on the model, this paper defined the cost elements of the thermal power equipment, analyzed influences of the thermal power equipment. Finally, the model is applied to an instance to estimate various cost categories in each life phase, which were summed up to the life cycle cost of the thermal power equipment.

Lower Mekong Basin (LMB) experiences a recurrent drought phenomenon. However, few studies have focused on drought monitoring in this region due to lack of ground observations. The newly released Climate Hazards Group Infrared Precipitation with Station data (CHIRPS) with a long-term record and high resolution has a great potential for drought monitoring. Based on the assessment of CHIRPS for capturing precipitation and monitoring drought, this study aims to evaluate the drought condition in LMB by using satellite-based CHIRPS from January 1981 to July 2016. The Standardized Precipitation Index (SPI) at various time scales (1–12-month) is computed to identify and describe drought events. Results suggest that CHIRPS can properly capture the drought characteristics at various time scales with the best performance at three-month time scale. Based on high-resolution long-term CHIRPS, it is found that LMB experienced four severe droughts during the last three decades with the longest one in 1991–1994 for 38 months and the driest one in 2015–2016 with drought affected area up to 75.6%. Droughts tend to occur over the north and south part of LMB with higher frequency, and Mekong Delta seems to experience more long-term and extreme drought events. Severe droughts have significant impacts on vegetation condition.

Purpose This paper aims to study the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass. Design/methodology/approach The authors performed weight loss experiments, electrochemical experiments including the polarization curve and electrochemical impedance spectrum, corrosion morphology observation using scanning electron microscope (SEM) and atomic force microscope (AFM) and surface composition analysis via X-ray photoelectron spectroscopy (XPS) to analyze the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass by using quantum chemical calculation (Gaussian 09), molecular dynamics simulation (M-S) and Langmuir adsorption isotherm. Findings According to the results, imidazole-pyridine and its derivatives were found to be modest or moderately mixed corrosion inhibitors; moreover, they were spontaneously adsorbed on the metal surface in a single-layer, mixed adsorption mode. Originality/value The corrosion inhibition properties of pyrazolo-[1,2-a]pyridine and its derivatives on brass in sulfuric acid solution were analyzed through weight loss and electrochemical experiments. Moreover, SEM and AFM were simultaneously used to observe the corrosion appearance. Furthermore, XPS was used to analyze the surface. Then, Gaussian 09 and M-S were combined along with the Langmuir adsorption isotherm to investigate the corrosion inhibition mechanism of imidazole-[1,2-a]pyridine and its derivatives.

To determine the potential for improving biomass enzymolysis, a combined oxidization and liquid ammonia pretreatment (OD-LAT) was employed for bamboo. The effects of oxidant, bamboo ages, and species on the pretreatment effectiveness and subsequent enzymolysis were studied. Under the optimal OD-LAT pretreatment and enzymolysis of the B-NA bamboo Neosinocalamus affinis, the glucan and xylan conversion reached 83.85% and 78.66%, respectively, and approximately 59.7-68.5 g of fermentable sugars can be produced per 100 g of dry bamboo, which was an approximately 5-8 fold increase compared with untreated sample. The H2O2 loading of 1.0 was the optimal oxidant dosage for the OD-LAT process. The OD-LAT pretreatment was only suitable for bamboo under three-year-old, and it significantly improved the enzymolysis of B-NA and B-BM, while it was limited to B-DO and B-PP. The pretreatment effects of bamboo were not only related to composition but also to the bamboo age, species, macro-structures and micro-structures.

A template‐agent can affect defect formation as well as influence interface properties, due to the rapid growth of perovskite film from the solution. Herein, diethylammonium iodide (DAI) is used as an effective template‐agent to control the perovskite crystallization during preparation. It is found that a very small amount of DAI in chlorobenzene (CB) can slow down the perovskite growth of the CH3NH3PbI3 (MAPbI3) film with more large grain size and compacted crystal‐grains resulting in the lesser grain boundaries (GBs) in favor of carrier transport in perovskite solar cells (PSCs). Moreover, some redundant PbI2 can be digested to form DA2PbI4. One part of DA2PbI4 can form the sub‐grains with the composition of (DA2PbI4)0.2(PbI2)0.8 to passivate the GB defects, and other part can cover the surface to passivate the surface defects in large MAPbI3 grains. Using an optimized DAI concentration of 0.5 mg mL−1 in CB solution, the corrsponding MAPbI3 PSC achieves an increased power conversion efficiency of 20.31% with suppressed current–voltage hysteresis. This DAI passivation strategy provides a simple approach to effectively assist the grain‐growth for improved device performance.

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.