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The effects of the number of imidazoline ring and the length of alkyl group chain of imidazoline derivatives were investigated using quantum chemical calculation, molecular dynamics simulation and experimental techniques. Three corrosion inhibitors including Symmetrical lauric acid imidazoline (SAI), Tetracyclic lauric acid imidazoline (LAI), and Symmetric stearic acid imidazoline (SPI) were synthesized and their inhibition performance was evaluated using weight loss measurement, electrochemical techniques and surface characterization. The results show that SAI and LAI with the same length of alkyl group chain, LAI with more imidazoline rings could supply a better inhibition performance since the increase of active sites. The increase of active sites attached to the metal surface may also change the distribution of corrosion inhibitor, which could limit inhibition performance improvement. While, SAI and SPI with the same number of imidazoline rings, SPI with longer alkyl group chain shows a better inhibition efficiency due to the better hydrophobic performance of alkyl groups. Among the three inhibitors, SPI show the best inhibition performance, indicating that the alkyl group chain length affects the inhibition performance more obvious than the number of the imidazoline rings.

We investigated erosion-corrosion (E-C) and its mitigation on the internal surface of the expansion segment of N80 steel tube in a loop system using array electrode technique, weight-loss measurement, computational-fluid-dynamics simulation, and surface characterization techniques. The results show that high E-C rates can occur at locations where there is a high flow velocity and/or a strong impact from sand particles, which results in different E-C rates at various locations. Consequently, it can be expected that localized corrosion often occurs in such segments. The E-C rate at each location in the expansion segment can be significantly mitigated with an imidazoline derivative inhibitor, as the resulting inhibitor layer significantly impedes the electrochemical reaction rate. However, we found that this inhibitor layer could not effectively reduce the difference in the erosion rates at different locations on the internal surface of the expansion segment. This means that localized corrosion can still occur at the expansion segment despite the presence of the inhibitor.

The industrialization process in China has resulted in the fast growth of the country’s energy consumption and CO2 emissions. Examining the effects of industrial structural change on the emissions pathways in the mid-term future would help advance understanding of how industrial policy choices affect the fulfillment of the strategic climate targets of emissions peaking and carbon neutrality. This study couples index decomposition analysis (IDA) with an additive nonparametric regression model to project the possible emissions pathways with different industrial structures. It develops a set of scenarios following the storylines of shared socioeconomic pathways (SSPs) to examine these effects in an uncertain environment towards 2040. The results show that structural change has played an increasing role in curbing carbon emissions of China’s industrial sectors since 2000. The CO2 emissions reductions attributable to this effect were 686 million tons (Mton CO2) between 2000 and 2013, and these contributions to emission mitigation rose to 798 Mton between 2014 and 2019. The scenario results suggest that the aggregated effect of energy efficiency and structure upgrades will decrease emissions by 43% in 2040 relative to the level in 2019 in the ideal case. Regardless of the uncertainties in scenario settings, heavy industry will continue to dominate China’s industrial emissions through 2040. Nevertheless, a significant structural change with an increased share of high-tech industries, such as information and communication technology, could lead to more than a 30% reduction in emissions compared to cases with more minor changes in this sub-sector. Key Policy InsightsA rapid expansion of heavy industry is the primary factor driving the rapid growth of China’s industrial CO2 emissions since 2000. Industrial structural change is the second most significant factor curbing emissions growth, and the influence of this factor is increasing.Keeping up the momentum of structural change and technological upgrades in the industrial sector would make it possible for industry emissions to decrease in the medium-term future, therefore contributing substantially to China’s goal of peaking its CO2 emissions by 2030.Realizing carbon neutrality in the longer term necessitates not only structural change in industry, but also a fundamental transformation of the energy supply system. A rapid expansion of heavy industry is the primary factor driving the rapid growth of China’s industrial CO2 emissions since 2000. Industrial structural change is the second most significant factor curbing emissions growth, and the influence of this factor is increasing. Keeping up the momentum of structural change and technological upgrades in the industrial sector would make it possible for industry emissions to decrease in the medium-term future, therefore contributing substantially to China’s goal of peaking its CO2 emissions by 2030. Realizing carbon neutrality in the longer term necessitates not only structural change in industry, but also a fundamental transformation of the energy supply system.

Both the sluggish redox kinetics and severe polysulfide shuttling behavior hinders the commercialization of lithium-sulfur (Li-S) battery. To solve these obstacles, we design a cobalt sulfide nanoparticle-embedded flexible carbon nanofiber membrane (denoted as CoS2@NCF) as sulfiphilic functional interlayer materials. The hierarchically porous structure of carbon nanofiber is conducive to immobilizing sulfur species and facilitating lithium-ion penetration. Moreover, electrocatalytic CoS2nanoparticles can significantly enhance the catalytic effect, achieving favorable adsorption-diffusion-conversion interface of polysulfide. Combined with these synergistic features, the assembled Li-S cell with CoS2@NCF interlayer exhibited a great discharge capacity of 950.9 mAh g-1with prolonged cycle lifespan at 1 C (maintained 648.1 mAh g-1over 500 cycles). This multifunctional interlayer material used in this contribution provides an advanced route for developing high-energy-density Li-S battery.

Objective: The present study was to compare the incidence of septal defect (SD) in patients with atrial fibrillation (AF) who received radiofrequency ablation or cryoablation. Methods: A total of 293 AF patients were performed with radiofrequency ablation and cryoablation. Cardiac ultrasonography was performed to calculate left atrial diameter (LAD), left atrial ejection fraction (LAEF%), strain rate (SR), left ventricular systolic (SRs), left ventricular diastolic (SRe), and left atrial systole (SRa) before surgery, 3 months and 1 year after surgery. The patients were followed up to observe statin and angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) medication, AF recurrence, 6-min walk test, stroke, any symptoms caused by arrhythmia, and re-hospitalization. Results: The levels of LAD and SD were higher, while SRe and SRa were lower in the cryoablation group in the comparison with the radiofrequency ablation group after surgery (P

Due to the significant speed advantage, air freight has become the preferred long-distance transportation method for precision electronic instruments and other high-value products. In order to avoid the impact of air load conditions on the safety of cargo and aircraft, it is necessary to calculate and check the carrying capacity of cargo package. In this paper, finite element analysis has been applied on design of an air freight package. Firstly, make force analyze, and use the maximum force for static analysis to solve stress distribution. Then, make modal analysis and random vibration analysis to obtain the 3σ stress and deformation. According to static analysis, the maximum equivalent stress of the package under emergency conditions is less thanσb. According to dynamic analysis, the probability that the maximum stress of the package is greater than 56.69Mpa does not exceed 0.3%.

Restoration of sinus rhythm in atrial fibrillation (AF) by radiofrequency catheter ablation (RFCA) is associated with a transient stunning of left atrial (LA) function. However, the long-term effects of different ablation strategies on LA function remain undetermined. We performed randomized controlled trial to evaluate the effects of RFCA, cryoablation, and 3D mapping-guided cryoablation on LA function of proximal AF patients within 1 year. The 3D mapping-guided cryoablation was defined as a maximum of two cryoablation procedures for each pulmonary vein accompanied by RFCA for additional points until complete pulmonary vein isolation was achieved. Conventional and speckle tracking echocardiographic analyses were performed to evaluate LA function. Among the 210 patients (70 in each group) included, a trend of decreasing LA systolic and diastolic function was observed in all groups, as evidenced by decreases in peak A-wave velocity, the global LA peak systolic strain, the peak strain rate, the peak early diastolic strain rate, and the peak late diastolic strain rate within 7 days to 3 months after ablation followed by gradual recovery thereafter. However, the temporal changes in the above four strain parameters among the three groups did not differ significantly within 1 year after ablation (all p > 0.05). Parameters of the LA emptying fraction and LA dimensions were not significantly affected. These results suggested that stunning of LA function occurred within 7 days to 3 months after ablation, and different strategies of AF ablation did not differentially affect the temporal changes in LA function up to 1 year after ablation.

The corrosion inhibition of carbon steel in CO2-O2-containing environment is one of the biggest challenges in flue gas injection for enhanced oil recovery. Herein we report the possibility to use Bis(2-ehylhexyl) phosphate (BEP) to inhibit the corrosion in CO2-O2-containing solution and simultaneously the inhibition mechanisms are unmasked. The results show that the corrosion is greatly inhibited with 500 ppm BEP in 1 wt% NaCl solution with 0.02 MPa CO2 and 3 mg/L O2. BEP could interact with Fe and corrosion products via the formation of P-O-Fe bond and P-Fe bond to generate a barrier layer, thus, offering a protective performance.

Hexagonal boron nitride (h-BN) was adopted to modify graphene oxide (GO) by silane agent chemically and the h-BN modified GO (BmGO) was used to improve the corrosion resistance of water-borne epoxy coating on hot-dip galvanized steel. It was found the dispersion of BmGO in ethanol was improved because of the increase of the crystal spacing of GO. The corrosion potential of coating containing BmGO (BmGO-EP) shifted from −0.96 V to −0.85 V and the corrosion current density was one order of magnetic higher than that of pour epoxy coating. Moreover, EIS results show that BmGO-EP performed the maximum |Z|f=0.01 and phased angle. Another time constant appeared after immersion in corrosive solution for 72 h. The improved corrosion resistance was because of the excellent dispersity of BmGO, which benefited modifying surface defects and extending the diffusion path of corrosive ions.

Superhydrophobic surfaces containing nano–SiO2 with excellent water repellency and wonderful corrosion resistance were prepared by a simple one–step immersion process on galvanized steel. The addition of SiO2 promotes the formation of surface rough structure efficiently, and the as–prepared surfaces exhibit good superhydrophobic property. Sample with 1 wt% SiO2 (Ms–1) attained contact angle reaching to 160.1 ± 2° and the corrosion current density with 8.34 × 10−8 A·cm−2, which is three orders of magnitude lower than galvanized steel. Due to the good shielding property and stability of SiO2, the anti–corrosion efficiency of Ms–1 has reached 99.6% in 3.5 wt% NaCl solution. The corrosion resistance of Ms–1 immersion for 48 h is better than untreated sample and after immersion for a week, the CA is still above 120°. The superhydrophobic surface with SiO2 can effectively improve the corrosion protection and hydrophobicity of galvanized steel.

In recent years, structural optimization design and computer-aided design methods have achieved long-term development. In order to achieve design innovation, improve product performance, and reduce production costs, enterprise pay more and more attention to the new design methods. Optimization design has become the key process of product development. Especially in the fields of aerospace, automobile that focus on lightweight and fuel saving, the scope and depth of topology optimization design is rapidly developing. In this paper, topology optimization has been applied on design of aircraft flip spreader, using ANSYS Workbench software to reduce the weight of the spreader. First, using static structural tool for static analysis, set loads and supports, solve the stress distribution of spreader under various working conditions. Then, using topology optimization tool for optimization design, set the optimization variables, constraints and objective, solve the optimal material distribution. At last, compared with traditional experience-based design methods, topology optimization design methods have obvious advantages, the weight of spreader has been reduced 25.5%, without affecting the component strength.

A gradual pipe contraction may cause severe localized corrosion resulted from the flow acceleration, thus threating the operating safety of pipelines in the oil and gas field. Until now, the quantitative study on the correlation between local corrosion rate and local hydrodynamics at the gradual pipe contraction is still missing. In this work, the flow accelerated corrosion and its mitigation at different locations of a gradual pipe contraction of N80 steel are in situ investigated using computational fluid dynamics simulation and array electrode technique combined with electrochemical impedance spectroscopy. The results show that the distribution of corrosion rate at the gradual pipe contraction is in good accordance with the distribution of hydrodynamics parameters including flow velocity and wall shear stress, i.e., the higher flow velocity or higher wall shear stress is, the higher local corrosion rate is. The presence of an imidazoline derivative inhibitor can greatly mitigate the corrosion at the gradual pipe contraction through hindering the mass transfer process and charge transfer process of corrosion. Furthermore, in the presence of inhibitor the differences in corrosion rate among different locations at the gradual pipe contraction are also effectively reduced, or even disappeared at low flow velocity. Therefore, the addition of the inhibitor is an effective way to mitigate or even eliminate the flow accelerated corrosion at the gradual pipe contraction in the oil and gas field.

Zhang, Y.; Zhang, C.; Li, C.; Yuan, C.; Pan, X., and Shi, L., 2019. The instability of deep-water sideband perturbation wave trains. In: Hoang, A.T. and Aqeel Ashraf, M. (eds.), Research, ...

With the announcement of open information policy by the Chinese government, there has been lots of development in government statistics, Census data, and GIS data. That information provides rich reference for regional analysis in China. The primary challenges under rapid data growth include how to efficiently integrate those space-time data, provide methodology for different research targets, and promote their applications in different fields. This report will present some recent developments of spatial intelligence technologies for spatial data integration, data analysis, as well as their applications. The report will introduce the newly developed spatial explorer (China Geo-Explorer) as a joint effort by the University of Michigan China Data Center and Wuhan University. It will demonstrate how space-time data of different formats and sources can be integrated, visualized, analyzed and reported in a web based system. Some applications in disaster assessment, environment and health, cultural and religious studies will be discussed for China and global studies.

Analysis and identification of the pigment composition of the cultural relics is the key and difficult point in the field of the protection of cultural relics. In this paper, we use hyperspectral technology to make identification and analysis of three kinds of Commonly used green mineral pigment composition unharmed The characteristic wavelength of the extreme point and the inflection point are found by calculating the first derivative and the second order derivative of the spectral curve. The experiment uses three common green mineral pigments of Chinese traditional painting to analysis the spectral absorption characteristics. The effective characteristics of these three kinds of pigments were calculated by correlation coefficient. Finally, based on the extracted features, the decision tree is established to distinguish the mineral pigments.

With the announcement of open information policy by the Chinese government, there has been lots of development in government statistics, Census data, and GIS data. That information provides rich reference for regional analysis in China. The primary challenges under rapid data growth include how to efficiently integrate those space-time data, provide methodology for different research targets, and promote their applications in different fields. This report will present some recent developments of spatial intelligence technologies for spatial data integration, data analysis, as well as their applications. The report will introduce the newly developed spatial explorer (China Geo-Explorer) as a joint effort by the University of Michigan China Data Center and Wuhan University. It will demonstrate how space-time data of different formats and sources can be integrated, visualized, analyzed and reported in a web based system. Some applications in disaster assessment, environment and health, cultural and religious studies will be discussed for China and global studies.

1 GENERAL INSTRUCTIONS In order to know the mastery and understanding degree of the painting formation among students, 300 questionnaires were distributed to students in higher art college, then we received 300 replies. This surve y covered more than ten colleges, including many majors of art education. The results show that 97% of the students had c onfusion on the painting formation during artistic creation; and 90% of the students think it is necessary to start painting formation courses. This survey reveals the short of painting formation in traditional teaching and the desire for the knowledge of formation from the students. For a long time, huge barrier had been existed between exercise and creation in art teaching, and it ha s important relationship with the short of

The far-infrared absorption spectra of myoglobin powder at hydration levels between 3.6 and 42 wt % were measured with terahertz time-domain spectroscopy and Fourier transform infrared spectroscopy. Absorption is dominated by the water content, but even the driest specimens have a nearly continuous spectrum without identifiable sharp features. Inhomogeneous broadening plus the intrinsically high spectral density of vibrational modes in the region below 2.0 THz apparently combine to obscure the lowest frequency vibrational modes expected for protein molecules of this size. A continuous absorption spectrum for hydrated protein powders suggests that the absorption mechanisms are similar to those in liquid water, and hinders the spectroscopic identification of biomolecules in this frequency range.

Objective To establish a simple extraction, isolation and purification method for ginkgolide B from ginkgo leaf. Method The optimum conditions of extraction, isolation and purification were studied by taking the transfer rate of ginkgolide B as index. Result Ginkgo leaf was extracted with 70% ethanol for three times, the extracts were concentrated to remove ethanol and diluted by water till the crude drug density reached 0.1 g x mL(-1). The dilution was adsorbed with HPD-450 macroporous resin. The impurities were eluted with 20% ethanol and ginkgolide B was eluted with 80% ethanol. Then the 80% ethanol eluant was concentrated and crystallized. Finally the crude crystals were recrystallized with isopropanol. The purity of the ginkgolide B recrystallization was 95%. Conclusion The process was stable and easy to operate, which was suited to industrialized production.