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Heavy crude oil upgrading under a supercritical water environment has demonstrated to have diverse advantages. For commercial applications, it is necessary to develop mathematical models that can predict the reactive behavior of the different components of crude oil under these operating conditions. However, the consideration of different experimental and modeling approaches can significantly influence the determination and evaluation of reaction rates, which complicates providing essential insights into the reaction system and thus generates numerical simulations and strategies that allow for increasing the efficiency of these processes. Therefore, this study analyzes the effect of the supercritical water atmosphere on the diverse reactions among oil components as well as different kinetic modeling approaches reported in the literature to predict the yields of reactive compounds. Complex kinetic models were developed using proposed reaction schemes and experimental data obtained during the upgrading of heavy crude oil under supercritical water conditions. The predictions with the models show good agreement concerning the experimental data. In addition, it was shown that the conversion of asphaltenes to resins and gas compounds under supercritical conditions presents a significant increase in reaction rates compared with experiments under non-catalytic and catalytic thermal cracking conditions.

Defect Detection is one of the most important parts of Automatic Identification and Data transmission. Quick Response code (QRcode) is one of the most popular types of two-dimensional barcodes. It isachallenge to detect defect of various QRcode images efficiently and accurately. In this paper, we propose the procedure byaserial of carefully designed preprocessing methods. The defect detection procedure consists of QRcode identification, QRcode reconstruction, perspective transformation, image binarization, morphological operation, image matching, and Blob analysis. By these steps, we can detect defect of different types of QRcode images. The experiment results show that our method has stronger robustness and higher efficiency. Moreover, experiment results on QRcode images show that the prediction accuracy of proposed method reaches 99.07%with an average execution time of 6.592 ms. This method can detect defect of these images in real time.

The physical properties of microcapsules are strongly influenced by the synthetic conditions used for their preparation. To prepare microcapsules possessing a smooth surface morphology, high mechanical strength, and reduced permeability of the core material, in situ polymerization in an oil-in-water emulsion was performed using poly (urea–formaldehyde) and tetrachloroethylene as the shell and core materials, respectively. The influence of the synthetic conditions, including the initial pH value, concentration of wall material, concentration of NaCl, and heating rate, on the properties of the resulting microcapsules was investigated systematically by an orthogonal factorial design. The physical properties of the microcapsules were characterized using scanning electron microscopy and optical-photographic microscopy. The results showed that the concentration of shell material has a substantial effect on the mechanical strength of the microcapsules. Additionally, a slow heating rate and high initial pH value enhance the preparation of well-defined spherical microcapsules having excellent barrier properties. Finally, a moderate concentration of sodium chloride can remarkably improve the compactness of the capsule wall. The optimum conditions, determined on the basis of utilization of wall material, are as follows: initial pH value: 3.5; concentration of shell material: 3.6 × 10−2g/mL; heating rate: 0.5 °C/min; and concentration of sodium chloride: 5.0 × 10−2g/mL.

The impact of interbasin water transfer on environment is very significant. The affected area of the west route scheme of the South to North Water Transfer Project in China (SNWT) is located in the eastern Tibetan Plateau, where the altitude is high with frigid eco-environment. In this article, remote sensing and GIS are applied to analyze the natural environment and the natural environment index is established to express the natural conditions of the study area. After the natural environment index is divided into four grades and the features of each grade are analysed, some results are obtained for reference in environmental assessment of the west route of SNWT.

Hazards caused by detonation of hydrocarbon‐air mixtures are a continuing problem. Of the factors affecting detonation hazards of hydrocarbon‐air mixtures, additives play an important role. In this paper, a series of experiments are described addressing the influence of chemical additives on the detonation of some hydrocarbon‐air mixtures under confined (rectangle shock tube tests) conditions. The experimental results show that NT (nitric ether or RONO2), PO (1,2‐epoxypropane), and BPO (benzoyl peroxide) have a clear sensitizing effect on the detonation hazards of these mixtures. The mechanistic influence of additives is simply described, according to the chain reaction theory of detonation.

Hazards caused by detonation of hydrocarbon‐air mixtures have been a matter of concern for a long time. In this paper, critical initiation energy of detonation of some hydrocarbon air mixtures have been measured in confined (rectangle shock tube tests) and unconfined (plastic bag tests) condition. Based on the concept of explosion length, a formula for estimating the critical initiation energy of detonation under unconfined condition is presented. Detonation safety analysis of the studied hydrocarbons is carried out using the experimental results.

A method called "Spectral K-ratio spectrophotometry" was proposed. The method takes the K-coefficient dual-wavelength spectrophotometric method as the mathematical model in order to resolve the different nth-derivative spectral data at one wavelength to determine certain two components systems that their zeroth- (absorption) and nth-derivative spectra were all interfered seriously. Examples of the application of the proposed method were given.