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Studying casing corrosion mechanism and seeking alternative corrosion-resistant materials are the fundamental ways to slove the increasingly serious problem of casing corrosion in oilfields. Herein， by simulating the field corrosion conditions of Changqing Oilfield， the corrosion behavior of J55 and 3Cr materials in the environment of a CO2 partial pressure of 1.0 MPa， a H2S partial pressure of 0.3 MPa and a temperature of 60 ℃was studied. Additionally， the morphology and components of the corrosion products of these two materials were analyzed by means of scanning electron microscopy， energy spectroscopy and X-ray diffraction. Results showed that the enrichment of Cr element in the corrosion product film and the formation of Cr(OH)3 improved the stability and compactness of the corrosion products， making 3Cr exhibit better corrosion resistance than J55. In the environment containing both CO2 and H2S， H2S corrosion played a dominant role. The loose corrosion product film formed in CO2 corrosion made the uniform corrosion rates of J55 and 3Cr higher than those in environments containing H2S alone and containing both H2S and CO2.

Microalgae are considered promising sustainable feedstocks for the production of food, food additives, feeds, chemicals and various high-value products. Marine microalgae Phaeodactylum tricornutum, Isochrysis galbana and Nitzschia laevis are rich in fucoxanthin, which is effective for weight loss and metabolic diseases. The selection of microalgae species with outstanding nutritional profiles is fundamental for novel foods development, and the nutritional value of P. tricornutum, I. galbana and N. laevis are not yet fully understood. Hence, this study investigates and analyzes the nutritional components of the microalgae by chromatography and mass spectrometry, to explore their nutritional and industrial application potential. The results indicate that the three microalgae possess high nutritional value. Among them, P. tricornutum shows significantly higher levels of proteins (43.29%) and amino acids, while I. galbana has the highest content of carbohydrates (25.40%) and lipids (10.95%). Notwithstanding that P. tricornutum and I. galbana have higher fucoxanthin contents, N. laevis achieves the highest fucoxanthin productivity (6.21 mg/L/day) and polyunsaturated fatty acids (PUFAs) productivity (26.13 mg/L/day) because of the competitive cell density (2.89 g/L) and the advantageous specific growth rate (0.42/day). Thus, compared with P. tricornutum and I. galbana, N. laevis is a more promising candidate for co-production of fucoxanthin and PUFAs. [ABSTRACT FROM AUTHOR]

Building Information Modeling in Precast Concrete factory should consider the split design and production as a whole, so we should pay attention to import the production information into MES and achieve enterprise level application. This paper studied two methods of importing production information to Manufacturing Execution System, namely DXF drawing and U file. This paper studied how to match information of DXF drawing with MES’s layer, text information and title bar. This paper also studied the correct format of U file and the information that can be resolved by MES. The feasibility of this two methods was verified through the prefabricated building project “Jin-an Hong Bao 7#”, and the types of prefabricated components, information quality, efficiency and cost of the two methods are compared. Dxf drawing is able to cover all kinds of precast components, easy for new comers to master, but the drawing efficiency is low. Currently, U file only supports composite floor slab, and it has a long training period, but it also has extremely low error rate and extremely high drawing efficiency.PC factory should continue to improve u file, which can greatly improve work efficiency and reduce engineering errors.

Taking a prefabricated project as an example, this paper establishes a calculation and evaluation model of prefabricated building in the physical and chemical stages, and compares the carbon emission reduction between prefabricated buildings and cast-in-place concrete buildings, proposes the ways of carbon emission reduction and calculates them to determine the emission reduction effect. The results show that, compared with cast-in-place buildings, the carbon emissions of prefabricated buildings can be reduced by 2.65 kg/m² in the physical and chemical stages. [ABSTRACT FROM AUTHOR]

The removal of chlorobenzene using a dielectric barrier discharge (DBD) reactor coupled with CuO/γ-Al2O3 catalysts was investigated in this paper. The coupling of CuO enhanced the chlorobenzene degradation and complete oxidation ability of the DBD reactor, especially under low voltage conditions. The characterization of catalyst was carried out to understand the interaction between catalyst and plasma discharge. The effects of flow rate and discharge power on the degradation of chlorobenzene and the interaction between these parameters were analyzed using the response surface model (RSM). The analysis of variance was applied to evaluate the significance of the independent variables and their interactions. The results show that the interactions between flow rate and discharge power are not negligible for the degradation of chlorobenzene. Moreover, based on the analysis of byproducts, 4-chlorophenol was discriminated as the important intermediate of chlorobenzene degradation, and the speculative decomposition mechanism of chlorobenzene is explored. [ABSTRACT FROM AUTHOR]

According to observations, different visual objects have different salient features in different scenarios. Even for the same object, its salient shape and appearance features may change greatly from time to time in a long‐term tracking task. Motivated by them, an end‐to‐end feature fusion framework was proposed based on the Siamese network, named FF‐Siam, which can effectively fuse different features for adaptive visual tracking. The framework consists of four layers. A feature extraction layer is designed to extract the different features of the target region and search region. The extracted features are then put into a weight generation layer to obtain the channel weights, which indicate the importance of different feature channels. Both features and the channel weights are utilised in a template generation layer to generate a discriminative template. Finally, the corresponding response maps created by the convolution of the search region features and the template are applied with a fusion layer to obtain the final response map for locating the target. Experimental results demonstrate that the proposed framework achieves state‐of‐the‐art performance on the popular Temple‐Colour, OTB50 and UAV123 benchmarks. [ABSTRACT FROM AUTHOR]

The paper researches the external thermal insulation system used on steel structure house, which include the composition of external thermal insulation system, connection type between rock wool insulation decorative board and steel frame lightweight boar, and system testing of external thermal insulation. The external thermal insulation system has very good prospect, because of these advantages, such as good insulation effect, good fire resistance, safe connection, and high construction efficiency. [ABSTRACT FROM AUTHOR]